inflecting

Inflecting is the act or process of adding inflection to a word to express grammatical features. In linguistics, inflection refers to changes in the form of a word that encode grammatical categories such as tense, number, person, mood, case, gender, aspect, voice, or definiteness. Inflecting languages use affixes, internal modifications, or both to mark these categories, while the core lexeme may be unchanged or only lightly altered. Inflection contrasts with derivation, which creates new words or shifts lexical category rather than signaling grammatical relations.

In practice, inflecting occurs on nouns, pronouns, adjectives, verbs, and—less commonly—other parts of speech. Noun inflection often marks number and case; pronouns may show person and case; adjectives may agree with nouns in gender, number, and case. Verb inflection marks tense, aspect, mood, voice, person, and number, producing conjugations. English has relatively simple inflection compared with highly synthetic languages like Russian or Latin, which have extensive noun declensions and verb conjugations. Agglutinative languages (e.g., Turkish, Swahili) often express multiple grammatical categories per word with several affixes, while fusional languages (e.g., Spanish, Russian) encode several features within single affixes.

Inflection can involve regular affixes, alternations (ablaut), suppletion, or stem changes. Some languages are analytic with little inflection and rely on word order and function words, while others are highly inflecting, employing rich morphological paradigms. The study of inflection spans morphology, syntax, and typology, helping describe how languages encode grammatical relationships.