Perusadjektiivia

Perusadjektiivia is a term used in Finnish linguistics to denote the base or lemma form of an adjective. It is the form that appears in dictionaries and grammar references as the core meaning of the adjective, from which all other inflected forms are derived. In everyday language, speakers may encounter the same word in different inflected shapes, but the perusadjektiivia remains the reference form.

In Finnish, adjectives do not have gender and must agree with the noun in number and case. The perusadjektiivia provides the stem that carries the core meaning and to which endings are attached to express singular or plural, and the various grammatical cases (such as nominative, genitive, partitive). The exact inflected forms depend on phonological properties of the stem, including vowel harmony and, for some adjectives, consonant gradation.

Adjectives form degrees of comparison from the perusadjektiivia. The comparative is typically built with suffixes like -mpi (for many adjectives) to yield forms such as isompi or kauniimpi. The superlative is usually expressed with forms like -in or irregular patterns (for example, isoin, kaunein; good becomes parempi, paras in common usage). Some adjectives follow less regular patterns, and their comparative or superlative forms may not be predictable from the base alone.

Examples illustrate the relationship between perusadjektiivia and inflected forms. The base adjective iso yields ison koira in inflected phrases (singular), or isot koirat in plural. Kaunis becomes kaunis nainen (singular) and kauniit naiset (plural). These inflections are built from the base form while preserving the essential meaning.

See also: Finnish grammar, adjectives, noun–adjective agreement.