inflectability

Inflectability is the property of a word that determines its potential to take inflectional forms. It is a feature of languages with morphologically rich systems and is not universal across all languages or all words. Inflectable items participate in inflectional paradigms that mark grammatical categories such as number, case, gender, tense, mood, aspect, person, and definiteness.

Inflection typically involves affixes attached to a base form, though internal vowel changes, umlaut, suppletion, or circumfixes may occur. The set of forms that a word can take constitutes its inflectional paradigm. Some words have full paradigms with many forms; others are partially inflectable or invariable (zero inflection). Regular inflection follows predictable patterns, while irregular inflection requires memorization.

Inflectability varies by word class and language. Nouns and pronouns often inflect for case and number; verbs inflect for tense, aspect, mood, person, and number; adjectives may inflect for degree or agreement. Some languages have extensive case systems (e.g., Finnish, Russian), while others rely more on word order and function words (e.g., Mandarin). Some languages display rich gender and agreement systems, increasing inflectability.

In linguistic study and natural language processing, inflectability affects lexicon design, parsing, and generation. Lexical entries may include lemmas and full inflectional paradigms or rules to construct inflected forms. Inflection generators and grammars rely on assumptions about a word's inflectability to produce correct surface forms.