In grammar, inflection or inflexion is the modification or marking of a word (or more precisely lexeme) to reflect grammatical (that is, relational) information, such as gender, tense, number or person. The concept of a "word" independent of the different inflections is called a lexeme, and the form of a word that is considered to have no or minimal inflection is called a lemma. An organized list of the inflected forms of a given lexeme is called an inflectional paradigm.

Examples in English

In English many nouns are inflected for number with the inflectional plural affix -s (as in "dog" → "dog-s"), and most English verbs are inflected for tense with the inflectional past tense affix -ed (as in "call" → "call-ed").

English also inflects verbs by affixation to mark the third person singular in the present tense (with -s), and the present participle (with -ing). English short adjectives are inflected to mark comparative and superlative forms (with -er and -est respectively).

In addition, English also shows inflection by ablaut (mostly in verbs) and umlaut (mostly in nouns), as well the odd long-short vowel alternation. For example:

• Write, wrote, written (ablaut, and also suffixing in the participle)
• Sing, sang, sung (ablaut)
• Foot, feet (umlaut)
• Mouse, mice (umlaut)
• Child, children (vowel alternation, and also suffixing in the plural)

In the past, writers sometimes gave words such as doctor, Negro, dictator, professor, and orator Latin inflections to mark them as feminine, thus forming doctress, Negress, dictatrix, professress, and oratress. These inflected forms were never frequently used, although many English users continue to use Latin endings today in somewhat more common constructions such as actress, waitress, executrix, and dominatrix.

German, which is related to English, employs many of these inflectional devices, but Umlaut and Ablaut are widespread, while in English they are considered more like exceptions.

Declension and conjugation

Two traditional grammatical terms refer to inflections of specific word classes:

• Declension: inflection of nouns, and often pronouns, adjectives, and determiners as well; often involving number, case, and/or gender; and
• Conjugation: inflection of verbs, often involving tense, mood, voice, and/or aspect, as well as agreement with one or more arguments in number, gender, and/or person.

Below is an example of a noun declension of the Latin noun vir 'man'. It is inflected for case and number with suffixes.

	Singular	Plural
Nom.	vir	vir-ī
Acc.	vir-um	vir-ōs
Gen.	vir-ī	vir-ōrum
Dat.	vir-ō	vir-īs
Abl.	vir-ō	vir-īs

Below is a conjugation of the verb hi 'arrive' in Lakota. It is inflected for person with prefixes and for number with the suffix -pi.

	Singular (/dual)		Plural
1st	wa-hi	'I arrive'	-
Inclusive (dual)	ų-hi	'you & I arrive'	ų-hi-pi	'we arrive'
2nd	ya-hi	'you arrive'	ya-hi-pi	'you all arrive'
3rd	hi	'he arrives'	hi-pi	'they arrive'

However, these two terms seem to be biased toward well-known dependent-marking languages (such as Spanish, Latin, German, Russian, Japanese etc.). In dependent-marking languages, nouns in adpositional phrases can carry inflectional morphemes. (Adpositions include prepositions and postpositions.) In head-marking languages, the adpositions can carry the inflection in adpositional phrases. This means that these languages will have inflected adpositions. In Western Apache (San Carlos dialect), the postposition -ká’ 'on' is inflected for person and number with prefixes.

	Singular		Dual		Plural
1st	shi-ká?	'on me'	noh-ká?	'on us two'	da-noh-ká?	'on us'
2nd	ni-ká?	'on you'	nohwi-ká?	'on you two'	da-nohwi-ká?	'on you all'
3rd	bi-ká?	'on him'	-		da-bi-ká?	'on them'

Traditional grammars have specific terms for inflections of nouns and verbs, but not for adpositions.

Inflection vs. derivation

Main article: Derivation (linguistics)

Inflection is the process of adding inflectional morphemes (atomic meaning units) to a word, which may indicate grammatical information (for example, case, number, person, gender or word class, mood, tense, or aspect). Compare with derivational morphemes, which create a new word from an existing word, sometimes by simply changing grammatical category (for example, changing a noun to a verb).

Words generally do not appear in dictionaries with inflectional morphemes. But they often do appear with derivational morphemes. For instance, English dictionaries list readable and readability, words with derivational suffixes, along with their root read. However, no traditional English dictionary will list book as one entry and books as a separate entry nor will they list jump and jumped as two different entries.

In some languages, inflected words do not appear in a fundamental form (the root morpheme) except in dictionaries and grammars.

Inflectional morphology

Main article: Inflectional morphology

Languages that add inflectional morphemes to words are sometimes called inflectional languages. Morphemes may be added in several different ways:

• Affixation, or simply adding morphemes onto the word without changing the root,
• Reduplication, doubling all or part of a word to change its meaning,
• Alternation, exchanging one sound for another in the root (usually vowel sounds, as in the ablaut process found in Germanic strong verbs and the umlaut often found in nouns, among others).
• Suprasegmental variations, such as of stress, pitch or tone, where no sounds are added or changed but the intonation and relative strength of each sound is altered regularly. For an example, see Initial-stress-derived noun.

Affixing includes prefixing (adding before the base), and suffixing (adding after the base), as well as the much less common infixing (inside) and circumfixing (a combination of prefix and suffix).

Inflection is most typically realized by adding an inflectional morpheme (that is, affixation) to the base form (either the root or a stem).

Relation to morphological typology

Main article: morphological typology

Inflection is sometimes confused with synthesis in languages. The two terms are related but not the same. Languages are broadly classified morphologically into analytic and synthetic categories, or more realistically along a continuum between the two extremes. Analytic languages isolate meaning into individual words, whereas synthetic languages create words not found in the dictionary by fusing or agglutinating morphemes, sometimes to the extent of having a whole sentence's worth of meaning in a single word. Inflected languages by definition fall into the synthetic category, though not all synthetic languages need be inflected.

Inflection in various languages

Uralic languages

The Uralic languages (comprising Finno-Ugric and Samoyedic) are agglutinative languages, following from the agglutination in Proto-Uralic. The largest languages are Hungarian, Finnish and Estonian, all European Union official languages. Uralic inflection is, or is developed from, affixing. Grammatical markers directly added to the word perform the same function as prepositions in English. Almost all words are inflected according to their roles in the sentence: verbs, nouns, pronouns, numerals, adjectives, and some particles.

Hungarian and Finnish, in particular, often simply concatenate suffixes. For example, Finnish talossanikinko "in my house, too?" consists of talo-ssa-ni-kin-ko. However, in the Finnic languages (Finnish, Estonian, Sami), there are processes which affect the root, particularly consonant gradation. The original suffixes may disappear (and appear only by liaison), leaving behind the modification of the root. This process is extensively developed in Estonian and Sami, and makes them also inflected, not only agglutinating languages. The Estonian accusative case, for example, is expressed by a modified root: maja →majja (historical form *majam).

Indo-European languages

All Indo-European languages, such as Albanian, English, German, Russian, Persian (Fârsi), Spanish, French, Sanskrit, and Hindi are inflected to a greater or lesser extent. In general, older Indo-European languages such as Latin, Irish, Latvian, Lithuanian, and more prominently Greek and Sanskrit in all their historical forms, are extensively inflected. Deflexion caused newer languages such as English and French to lose much of their historical inflection. Afrikaans, an extremely young language, is almost completely uninflected and borders on being analytic. Some branches of Indo-European (for example, the Slavic languages, the Celtic languages, and the Romance languages) have generally retained more inflection than others (such as many Germanic languages, with the notable exception of Icelandic).

English

Old English was a moderately inflected language, using an extensive case system similar to that of modern Icelandic or German. Middle and Modern English lost progressively more of the Old English inflectional system. Modern English is considered a weakly inflected language, since its nouns have only vestiges of inflection (plurals, the pronouns), and its regular verbs have only four forms: an inflected form for the past indicative and subjunctive (looked), an inflected form for the third-person-singular present indicative (looks), an inflected form for the present participle (looking), and an uninflected form for everything else (look). While the English possessive indicator 's (as in "Jane's book") is a remnant of the Old English genitive case suffix, it is now not a suffix but a clitic. See also Declension in English.

Other Germanic languages

Old Norse was inflected, but modern Swedish, Norwegian and Danish have, like English, lost almost all inflection. Icelandic preserves almost all of the inflections of Old Norse and has added its own. Modern German remains moderately inflected, retaining four noun cases, although the genitive began falling into disuse in the late 20th century in all but formal writing, inspiring the title of the 2004 bestseller Der Dativ ist dem Genitiv sein Tod ("the dative is the death of the genitive", using the dative where archaic or formal writing would use the genitive). The case system of Dutch, simpler than German's, is also becoming more simplified in common usage. Afrikaans, recognized as a distinct language in its own right rather than a Dutch dialect only in the early 20th century, has lost almost all inflection.

Latin and Romance languages

The Romance languages, such as Spanish, Italian, French, and Romanian, have more inflection than English, especially in verb conjugation. A single morpheme usually carries information about person, number, tense, aspect and mood, and the verb paradigm may be quite complex. Adjectives, nouns and articles are considerably less inflected, but they still have different forms according to number and grammatical gender.

Latin was even more inflected; nouns and adjectives had different forms according to their grammatical case (with several patterns of declension, and three genders instead of the two found in most Romance tongues), and there were synthetic perfective and passive voice verb forms.

East Asian languages

Some of the major Eastern Asian languages (such as the various Chinese languages, Vietnamese, and Thai) are not inflected, or show very little inflection (though they used to show more), so they are considered analytic languages (also known as isolating languages).

Japanese

Japanese shows a high degree of inflection on verbs, less so on adjectives, and very little on nouns, but it is always strictly agglutinative and extremely regular. Formally, every noun phrase must be marked for case, but this is done by invariable particles (clitic postpositions). (Many grammarians consider Japanese particles to be separate words, and therefore not an inflection, while others consider agglutination a type of inflection, and therefore consider Japanese nouns inflected.)

Basque

Basque, a language isolate, is an extremely inflected language, heavily inflecting both nouns and verbs. A Basque noun is inflected in 17 different ways for case, multiplied by 4 ways for its definiteness and number. These first 68 forms are further modified based on other parts of the sentence, which in turn are inflected for the noun again. It is estimated that at two levels of recursion, a Basque noun may have 458,683 inflected forms (Agirre et al, 1992). Verb forms are similarly complex, agreeing with the subject, the direct object and several other arguments.

Auxiliary languages

Many auxiliary languages have very simple inflectional systems. Interlingua, in contrast with the Romance languages, has no irregular verb conjugations, and its verb forms are the same for all persons and numbers. It does, however, have compound verb tenses similar to those in the Romance, Germanic, and Slavic languages: ille ha vivite, "he has lived"; illa habeva vivite, "she had lived". Nouns are inflected by number, taking a plural -s, but rarely by gender: only when referring to a male or female being. Interlingua has no noun-adjective agreement by gender, number, or case. As a result, adjectives ordinarily have no inflections. They may take the plural form if they are being used in place of a noun: le povres, "the poor".

References and recommended reading

• Agirre, E.; Alegria I.; Arregi, X.; Artola, X.; Díaz de Ilarraza, A.; Maritxalar M.; et al. (1992). XUXEN: A spelling checker/corrector for Basque based on two-level morphology. Proceedings of the Third Conference of Applied Natural Language Processing. Online version: http://acl.ldc.upenn.edu/A/A92/A92-1016.pdf
• Bauer, Laurie. (2003). Introducing linguistic morphology (2nd ed.). Washington, D.C.: Georgetown University Press. ISBN 0-87840-343-4.
• Bubenik, Vit. (1999). An introduction to the study of morphology. LINCON coursebooks in linguistics, 07. Muenchen: LINCOM Europa. ISBN 3-89586-570-2.
• Haspelmath, Martin. (2002). Understanding morphology. London: Arnold (co-published by Oxford University Press). ISBN 0340760257 (hb); ISBN 0-340-76206-5 (pbk).
• Katamba, Francis. (1993). Morphology. Modern linguistics series. New York: St. Martin's Press. ISBN 0-312-10101-5 (hb); ISBN 0-312-10356-5 (pbk).
• Matthews, Peter. (1991). Morphology (2nd ed.). Cambridge: Cambridge University Press. ISBN 0-521-41043-6 (hb); ISBN 0-521-42256-6 (pbk).
• Nichols, Johanna. (1986). Head-marking and dependent-marking grammar. Language, 62 (1), 56-119.
• De Reuse, Willem J. (1996). A practical grammar of the San Carlos Apache language. LINCOM Studies in Native American Linguistics 51. LINCOM. ISBN 3895868612
• Spencer, Andrew, & Zwicky, Arnold M. (Eds.) (1998). The handbook of morphology. Blackwell handbooks in linguistics. Oxford: Blackwell. ISBN 0-631-18544-5.
• Stump, Gregory T. (2001). Inflectional morphology: A theory of paradigm structure. Cambridge studies in linguistics. Cambridge: Cambridge University Press. ISBN 0-521-78047-0.
• Van Valin, Robert D., Jr. (2001). An introduction to syntax. Cambridge: Cambridge University Press. ISBN 0-521-63566-7 (pbk); ISBN 0-521-63199-8 (hb).

See also

• Agreement (linguistics)
• Synthetic language
• Morpheme
• Lexeme
• Marker (linguistics)
• Uninflected word

External links

• Inflection entry at Encyclopedia.com
• SIL: What is inflection?
• SIL: What is an inflectional affix?
• SIL: What is an inflectional category?
• SIL: What is a morphological process?
• SIL: What is derivation?
• SIL: Comparison of inflection and derivation
• Lexicon of Linguistics: Inflection, Derivation
• Lexicon of Linguistics: Conjugation, Declension
• Lexicon of Linguistics: Base, Stem, Root
• Lexicon of Linguistics: Defective Paradigm
• Lexicon of Linguistics: Strong Verb
• Lexicon of Linguistics: Inflection Phrase (IP), INFL, AGR, Tense
• Lexicon of Linguistics: Lexicalist Hypothesis
• SIL: What is an agglutinative language?
• SIL: What is a fusional language?
• SIL: What is an isolating language?
• SIL: What is a polysynthetic language?
• Lexicon of Linguistics: Agglutinating Language, Fusional Morphology, Isolating Language, Polysynthetic Language