- For the symbol of the erect penis, see phallus.
The
penis (plural
penises,
penes) is an external
sexual organ of certain biologically
male organisms. The penis is a
reproductive organ, technically an
intromittent organ, and for
mammals, additionally serves as the external organ of
urination.
Structure


An erect penis, shaved of its pubic hair
The human penis is made up of three columns of
tissue: two
corpora cavernosa lie next to each other on the
dorsal side and one
corpus spongiosum lies between them on the ventral side.
The end of the corpus spongiosum is enlarged and bulbous-shaped and forms the
glans penis. The glans supports the
foreskin or prepuce, a loose fold of skin that in adults can retract to expose the glans. The area on the underside of the penis, where the foreskin is attached, is called the
frenum (or frenulum).
The
urethra, which is the last part of the
urinary tract, traverses the corpus spongiosum and its opening, known as the
meatus, lies on the tip of the glans penis. It is a passage both for
urine and for the
ejaculation of
semen.
Sperm is produced in the
testes and stored in the attached
epididymis. During ejaculation, sperm are propelled up the
vas deferens, two ducts that pass over and behind the bladder. Fluids are added by the
seminal vesicles and the vas deferens turns into the
ejaculatory ducts which join the urethra inside the
prostate gland. The prostate as well as the
bulbourethral glands add further secretions, and the semen is expelled through the penis.
The
raphe is the visible ridge between the
lateral halves of the penis, found on the ventral or underside of the penis, running from the meatus (opening of the urethra) across the scrotum to the
perineum (area between scrotum and anus).
The human penis differs from those of most other mammals. It has no
baculum, or
erectile bone; instead it relies entirely on engorgement with blood to reach its erect state. It cannot be withdrawn into the groin, and is larger than average in the animal kingdom in proportion to body mass.
Linguistics
Etymology
The word "penis" was taken from
Latin and originally meant "
tail." Some derive that from
Indo-European *pesnis, and the Greek word πεος = "penis" from Indo-European
*pesos. Prior to the adoption of the Latin word in English the penis was referred to as a "yard". The
Oxford English Dictionary cites an examples of the word
yard used in this sense from 1379,
[1] and notes that in his
Physical Dictionary of 1684, Steven Blankaart defined the word
penis as "the Yard, made up of two nervous Bodies, the Channel, Nut, Skin, and Fore-skin, etc."
[2]
The Latin word
"phallus" (from
Greek φαλλος) is sometimes used to describe the penis, although "phallus" originally was used to describe
images, pictorial or carved, of the penis.
[3]
Slang
As with nearly any aspect of the human body that is involved in sexual or
excretory functions, the word penis is considered inherently funny from a juvenile perspective and there are many slang words for the penis, including "dick", "wang" or "cock". Many of these are noted in the bathroom humor article.
"Penii" is sometimes facetiously or mistakenly used as a plural form of "penis" instead of "penes" or "penises," its correct forms.
Puberty
When a boy enters
puberty, after the
testicles begin to develop, the penis begins to enlarge, alongside the rest of the genitals. The penis grows longer until about the age of 16, and growth in width begins at roughly the age of 11. During the process,
pubic hair grows above and around the penis.
Sexual homology
In short, this is a known list of sex organs that evolve from the same tissue in a human life.
The
glans of the penis is
homologous to the
clitoral glans; the corpora cavernosa are homologous to the body of the clitoris; the corpus spongiosum is homologous to the
vestibular bulbs beneath the labia minora; the scrotum, homologous to the
labia minora and
labia majora; and the foreskin, homologous to the
clitoral hood. The raphe does not exist in females, because there, the two halves are not connected.
Erection


An uncircumcised penis in both flaccid and fully erect states
An erection is the stiffening and rising of the penis, which occurs during
sexual arousal, though it can also happen in non-sexual situations. The primary physiological mechanism that brings about erection is the autonomic
dilation of
arteries supplying
blood to the penis, which allows more blood to fill the three spongy erectile tissue chambers in the penis, causing it to lengthen and stiffen. The now-engorged erectile tissue presses against and constricts the veins that carry blood away from the penis. More blood enters than leaves the penis until an equilibrium is reached where an equal volume of blood flows into the dilated arteries and out of the constricted veins; a constant erectile size is achieved at this equilibrium.
Erection facilitates
sexual intercourse though it is not essential for various other
sexual activities. Although many erect penises point upwards (see illustration), it is common and normal for the erect penis to point nearly vertically upwards or nearly vertically downwards or even horizontally straightforward, all depending on the tension of the suspensory
ligament that holds it in position. Stiffness or erectile angle can vary.
Size
As a general rule, an
animal's penis is proportional to its body size, but this varies greatly between
species — even between closely related species. For example, an adult
gorilla's erect penis is about 4 cm (1.5 in) in length; an adult
chimpanzee, significantly smaller (in body size) than a gorilla, has a penis size about double that of the gorilla. In comparison, the
human penis is larger than that of any other
primate, both in proportion to body size and in absolute terms.
While results vary across studies, the consensus is that the average human penis is approximately 12.7-15 cm (5-5.9 in) in length
[4][5][6] and 12.3 cm (4.85 in) in
circumference when fully
erect. The
average penis size is slightly larger than the
median size. Most of these studies were performed on subjects of primarily European descent. Worldwide averages may vary.
A research project, summarizing dozens of published studies conducted by physicians of different nationalities, shows that worldwide, erect-penis size averages vary between 9.6 cm (3.7 in) and 16 cm (6.2 in). It has been suggested that this difference is caused not only by
genetics, but also by environmental factors such as
culture,
diet, chemical/pollution exposure
[7][8], etc.
As with any other bodily attribute, the length and girth of the penis can be highly variable between individuals of the same species. In many animals, especially
mammals, the size of a flaccid penis is much smaller than its erect size. In humans and some other species, flaccid vs. erect penis size varies greatly between individuals, such that penis size when flaccid is not a reliable predictor of size when erect.
Except for extreme cases at either end of the size spectrum, penis size does not correspond strongly to reproductive ability in almost any species.
Normal variations
Depending on temperature, a flaccid (not erect) penis of average size can withdraw almost completely within the body. During erection the penis will return to its normal (erect) size.
- Other variations:
- Pearly penile papules are raised bumps of somewhat paler color around the base of the glans and are normal.
- Fordyce's spots are small, raised, yellowish-white spots 1-2 mm in diameter that may appear on the penis.
- Sebaceous prominences are raised bumps similar to Fordyce's spots on the shaft of the penis, located at the sebaceous glands and are normal.
- Phimosis is an inability to retract the foreskin fully, is harmless in infancy and pre-pubescence, occurring in about 8% of boys at age 10. According to the British Medical Association, treatment (steroid cream, manual stretching) does not need to be considered until age 19.
- Curvature: few penises are completely straight with curves commonly seen in all directions (up, down, left, right). Sometimes the curve is very prominent but it rarely inhibits sexual intercourse. Curvature as great as 30° is considered normal and medical treatment is rarely considered unless the angle exceeds 45°. Changes to the curvature of a penis may be caused by Peyronie's disease.
Disorders affecting the penis
Edema (swelling) of the foreskin can result from sexual activity, including masturbation.
Paraphimosis is an inability to move the foreskin forward, over the glans. It can result from fluid trapped in a foreskin which is left retracted, perhaps following a medical procedure, or accumulation of fluid in the foreskin because of
friction during vigorous sexual activity.
In
Peyronie's disease, anomalous scar tissue grows in the soft tissue of the penis, causing curvature. Severe cases can benefit from surgical correction.
A
thrombosis can occur during periods of frequent and prolonged sexual activity, especially fellatio. It is usually harmless and self-corrects within a few weeks.
Infection with the
Herpes virus can occur after sexual contact with an infected carrier; this may lead to the development of herpes sores.
Pudendal nerve entrapment is a condition characterized by pain on sitting and loss of penile (or clitoral) sensation and orgasm. Occasionally there is a total loss of sensation and orgasm. The
pudendal nerve can be damaged by narrow hard bicycle seats and accidents.
Penile fracture can occur if the erect penis is bent excessively. A popping or cracking sound and pain is normally associated with this event. Emergency medical assistance should be obtained. Prompt medical attention lowers likelihood of permanent penile curvature.
In
diabetes,
peripheral neuropathy can cause tingling in the penile skin and possibly reduced or completely absent sensation. The reduced sensations can lead to injuries for either partner and their absence can make it impossible to have sexual pleasure through stimulation of the penis. Since the problems are caused by permanent nerve damage, preventive treatment through good control of the diabetes is the primary treatment. Some limited recovery may be possible through improved diabetes control.
Erectile dysfunction or
impotence is the inability to have and maintain an erection sufficiently firm for satisfactory sexual performance. Diabetes is a leading cause, as is natural aging. A variety of treatments exist, including drugs, such as
sildenafil citrate (marketed as
Viagra) which works by
vasodilation.
Priapism is a painful and potentially harmful medical condition in which the erect penis does not return to its flaccid state. The causative mechanisms are poorly understood but involve complex neurological and vascular factors. Potential complications include ischaemia, thrombosis, and impotence. In serious cases the condition may result in
gangrene, which may necessitate
amputation.
Lymphangiosclerosis is a hardened
lymph vessel, although it can feel like a hardened, almost calcified or fibrous, vein. It tend to not share the common blue tint with a vein however. It can be felt as a hardened lump or "vein" even when the penis is flaccid, and is even more prominent during an erection. It is considered a
benign physical condition. It is fairly common and can follow a particularly vigorous sexual activity for men and tend to go away if given rest and more gentle care, for example by use of lubricants.
Developmental disorders of the penis
Hypospadias is a
developmental disorder where the
meatus is positioned wrongly at birth. Hypospadias can also occur
iatrogenically by the downward pressure of an indwelling urethral catheter.
[9] It is usually corrected by surgery. The Intersex Society of North America classifies hypospadias as an intersex condition. They believe in halting all medically unnecessary surgeries, including many of those done on people with hypospadias.
A
micropenis is a very small penis caused by developmental or congenital problems.
Diphallia, or penile duplication (PD), is the condition of having two penises. However, this disorder is exceedingly rare.
Alleged and observed psychological disorders
Altering the genitalia
The most prevalent form of genital alteration in some countries is
circumcision: removal of part or all of the foreskin for various cultural, religious, and more rarely medical reasons. In many cases, such as in some
United States hospitals, the
frenulum and part of the shaft skin is also removed.
Less commonly, the penis is sometimes
pierced or decorated by other
body art. Other than circumcision, genital alterations are almost universally elective and usually for the purpose of aesthetics or increased sensitivity. Piercings of the penis include the
Prince Albert piercing, the
apadravya piercing, the
ampallang piercing, the
dydoe piercing, and the
frenum piercing.
Foreskin restoration or stretching is a further form of
body modification.
Other practices which alter the penis are also performed, although they are rare in Western societies without a diagnosed medical condition. Apart from a
penectomy, perhaps the most radical of these is
subincision, in which the urethra is split along the underside of the penis. Subincision originated among
Australian Aborigines, although it is now done by some in the U.S. and Europe.
Penis replacement
The first successful penis allotransplant surgery was done on September 2005 in a military hospital in
Guangzhou, China.
[10] A man at 44 sustained an injury after an accident and his penis was severed;
urination became difficult as his urethra was partly blocked. A newly
brain-dead man, at 23, was tracked down and his penis selected for the transplant. Despite
atrophy of blood vessels and nerves, the
arteries,
veins, nerves and the corpora spongiosa were successfully matched. On September 19th, the surgery was reversed because of a severe
psychological problem of the recipient and his wife.
[11]
Non-human penises
Most
marsupials, except for the two largest species of
kangaroos, have a
bifurcated penis. That is, it separates into two columns, and so the penis has two ends.
Urban legend alleges that the
dolphin has
prehensile control over his penis (it is true, however, that whales and dolphins can move and to a certain degree bend their penis tips to facilitate mating). In the realm of absolute size, the smallest vertebrate penis belongs to the
common shrew (5 mm or 0.2 inches). The largest penis belongs to the
blue whale estimated at over 2 m (more than 6½ feet). Accurate measurements are difficult to take because the whale's erect length can only be observed during mating.
Gorillas have relatively small penises, so it is an often used subtle insult in some countries to insinuate or directly state that one is 'hung like a gorilla'.
The
Icelandic Phallological Museum is devoted entirely to collecting penis specimens from all sorts of land and sea mammals. The museum has received a legally-certified gift token for a future specimen belonging to
Homo sapiens.
Among birds, only
paleognathes (
tinamous and
ratites) and
Anatidae (ducks, geese and swans) possess a penis. It is different in structure from mammal penises, being an erectile expansion of the
cloacal wall and being erected by
lymph, not blood. It is usually partially feathered and in some species features spines and brush-like filaments, and in flaccid state curled up inside the cloaca. The
Argentine Blue-bill has the largest penis in relation to body size of all vertebrates; while usually about half the body size (20 cm), a specimen with a remarkable 42.5 cm-long penis is documented.
Male specimens of the
Squamata order of reptiles have two paired organs called
hemipenes. In fish, the gonopodium,
andropodium, and
claspers are various organs developed from modified fins. In male
insects, the structure homologous to a penis is known as
aedeagus. The male copulatory organ of various lower invertebrate animals is often called the
cirrus.
Cultural aspects involving penises
Uses of animal penises
- Culinary, e.g., in Chinese gastronomy
- Magical and therapeutic, in medicine and/or superstition, especially as an alleged aphrodisiac or even cure for impotence
- Also used for punitive implements and dog toys, such as the bull pizzle
Uses of human penises in cultural traditions
- Aesthetical, e.g., Body modification
- For the symbolic and artistic use, see under phallus; in heraldry, the term is pizzle
- In humor, considered indecent or completely taboo in various cultures
References
1.
^ Simpson, John & Edmund Weiner, eds. (1989), "yard, n.2", Oxford English Dictionary (2nd ed.), Oxford University Press, Online edition, print version ISBN 978-0-19-861186-8, CD-ROM ISBN 978-0-19-861016-8
2.
^ Simpson, John, ed. (2005), "penis, n.", Oxford English Dictionary (Draft revision September 2005 ed.), Oxford University Press, Online edition (1989 second edition: ISBN 978-0-19-861186-8, CD-ROM ISBN 978-0-19-861016-8)
3.
^ Online Etymology Dictionary
4.
^ Wessels, H (1996-9-1).
Penile Length in the Flaccid and Erect States: Guidelines for Penile Augmentation. Retrieved on 2007-06-05.
5.
^ Chen, J (2000-12-1).
Predicting penile size during erection. Retrieved on 2006-09-23.
6.
^ ANSELL RESEARCH - The Penis Size Survey (March 2001). Retrieved on 2006-07-13.
7.
^ Size decrease in Male infants with prenatal phthalate exposure.
ehp. Retrieved on 2006-11-08.
8.
^ PCBs DIMINISH PENIS SIZE. Retrieved on 2007-04-09.
9.
^ Iatrogenic hypospadias--a preventable injury?
10.
^ Guangzhou Daily
11.
^ [1]
See also
External links
| Male reproductive system |
|---|
| Scrotum | layers (skin, Dartos, External spermatic fascia, Cremaster, Internal spermatic fascia) • Perineal raphe • Spermatic cord |
|---|
| Testes | layers (Tunica vaginalis, Tunica albuginea) • Appendix • Mediastinum • Lobules • Septa • Leydig cell • Sertoli cell • Blood-testis barrier |
|---|
| Spermatogenesis | Spermatogonium • Spermatocytogenesis • Spermatocyte • Spermatidogenesis • Spermatid • Spermiogenesis • Spermatozoon |
|---|
| seminal tract | Seminiferous tubules (Tubuli seminiferi recti, Rete testis, Efferent ducts) • Epididymis (Appendix) • Vas deferens • Ejaculatory duct Seminal colliculus |
|---|
| urinary tract | Internal urethral orifice • Urethra (Prostatic, Intermediate, Spongy) • Urethral crest • Urethral gland • External urethral orifice |
|---|
| Penis | Corpus cavernosum • Corpus spongiosum • Navicular fossa of male urethra • Glans penis • Fundiform ligament • Suspensory ligament • Foreskin • Frenulum |
|---|
| accessory glands | Seminal vesicles (Excretory duct of seminal gland) • Prostate (Prostatic utricle, Prostatic sinus) • Bulbourethral glands
|
|---|
Latin}}}
Official status
Official language of: Vatican City
Used for official purposes, but not spoken in everyday speech
Regulated by: Opus Fundatum Latinitas
Roman Catholic Church
Language codes
ISO 639-1: la
ISO 639-2: lat
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Arteries are muscular blood vessels that carry blood away from the heart.[1] All arteries, with the exception of the pulmonary and umbilical arteries, carry oxygenated blood.
The circulatory system is extremely important for sustaining life.
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The Dorsal Artery of the Penis ascends between the crus penis and the pubic symphysis, and, piercing the inferior fascia of the urogenital diaphragm, passes between the two layers of the suspensory ligament of the penis, and runs forward on the dorsum of the penis to the glans,
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The deep artery of the penis (artery to the corpus cavernosum), one of the terminal branches of the internal pudendal, arises from that vessel while it is situated between the two fasciæ of the urogenital diaphragm (deep perineal pouch).
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The artery of the urethral bulb (artery of bulb of penis, bulbourethral artery) is a short vessel of large caliber which arises from the internal pudendal between the two layers of fascia of the urogenital diaphragm; it passes medialward, pierces the inferior fascia
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vein is a blood vessel that carries blood toward the heart. The majority of veins in the body carry low-oxygen blood from the tissues back to the heart; the exceptions being the pulmonary and umbilical veins which both carry oxygenated blood.
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Dorsal veins of the penis can refer to:
- superficial dorsal vein of the penis
- deep dorsal vein of the penis
..... Click the link for more information. A nerve is an enclosed, cable-like bundle of axons (the long, slender projection of a neuron). Neurons are sometimes called nerve cells, though this term is technically imprecise since many neurons do not form nerves, and nerves also include the glial cells that
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The dorsal nerve of the penis is the deepest division of the pudendal nerve; it accompanies the internal pudendal artery along the ramus of the ischium; it then runs forward along the margin of the inferior ramus of the pubis, between the superior and inferior layers of the fascia
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The lymphatic system is a complex network of lymphoid organs, lymph nodes, lymph ducts, lymphatic tissues, lymph capillaries and lymph vessels that produce and transport lymph fluid from tissues to the circulatory system.
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The superficial inguinal lymph nodes form a chain immediately below the inguinal ligament.
They lie along the saphenous vein (v. saphena magna), deep to Camper's fascia and superficial to the cribriform fascia which overlies the femoral vessels.
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Embryology is the study of the development of an embryo. An embryo is defined as any vertebrate in a stage before birth or hatching. Embryology refers to the development of the egg cell (zygote) after fertilization and the differentiation of cells into tissues and organs.
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A genital tubercle is a body of tissue present in the development of the urinary and reproductive organs. It forms in the ventral, caudal region of mammalian embryos of both sexes, and eventually develops into a phallus.
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The
urogenital folds (or
urogenital ridges, or
urethral folds) are an embryological structure which give rise to a portion of the external genitalia.
- In the female, the urogenital folds become the labia minora.
..... Click the link for more information. Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. Created and updated by the United States National Library of Medicine (NLM), it is used by the MEDLINE/PubMed
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phallus can refer to an erect penis, to a penis-shaped object such as a dildo, or to a mimetic image of an erect penis. Any object that symbolically resembles a penis may also be referred to as a phallus; however, such objects are more often referred to as being phallic
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A
sex organ, or
primary sexual characteristic, as narrowly defined, is any of those anatomical parts of the body which are involved in sexual reproduction and constitute the reproductive system in a complex organism; namely:
..... Click the link for more information. Male (♂) refers to the sex of an organism, or part of an organism, which produces small mobile gametes, called spermatozoa. Each spermatozoon can fuse with a larger female gamete or ovum, in the process of fertilisation.
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If you are prevented from editing this page, and you wish to make a change, please discuss changes on the talk page, request unprotection, log in, or .
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An intromittent organ is a general term for any an external organ of a male organism that is specialized to deliver sperm during copulation. Intromittent organs are found most often in terrestrial species, as most aquatic species fertilize their eggs externally, although there are
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MammaliaLinnaeus, 1758
Subclasses & Infraclasses
- Subclass †Allotheria*
- Subclass Prototheria
- Subclass Theria
..... Click the link for more information. Urination, known by physiologists as micturition, or more simply as voiding, is the process of disposing urine from the urinary bladder through the urethra to the outside of the body.
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Biological tissue is a collection of interconnected cells that perform a similar function within an organism.
The study of tissue is known as histology, or, in connection with disease, histopathology.
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The corpus cavernosum penis is one of a pair of sponge-like regions of erectile tissue which contain most of the blood in the male penis during erection. There are corresponding structures and functions in the female clitoris.
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In sciences dealing with the anatomy of animals, precise anatomical terms of location are necessary for a variety of reasons. Non-scientists often wonder why zoological and human anatomists use complex terminology to describe locations on a body, when common terms like "up",
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Corpus spongiosum (Plural: Corpora Spongiosa) (also known as corpus cavernosum urethrae in older texts) is the mass of spongy tissue surrounding the male urethra within the penis.
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The glans penis (or simply glans) is the sensitive tip of the penis. It is also commonly referred to as the "head" of the penis. Slang terms include "helmet" and "bell end".
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The foreskin or prepuce (a technically broader term that also includes the clitoral hood, the homologous structure in women) is a retractable double-layered fold of skin and mucous membrane that covers the glans penis and protects the urinary meatus when the penis is not
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- Frenula redirects here. For the brachiopod genus, see Frenula (brachiopod)
A
frenulum (or
frenum, plural:
frenula or
frena, from the Latin
frēnulum, "little bridle", the diminutive of
frēnum..... Click the link for more information. In anatomy, the urethra is a tube which connects the urinary bladder to the outside of the body. The urethra has an excretory function in both genders to pass urine to the outside, and also a reproductive function in the male, as a passage for sperm.
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