Perusmuodon

Perusmuoto is a term in Finnish grammar that refers to the base form of a word, used as the dictionary or citation form. It is the form from which other inflected forms are derived and serves as the standard reference form in grammar descriptions and lexicography.

For nouns, the perusmuoto is generally the singular nominative form. Examples include talo (house), kissa (cat) and opettaja (teacher). From these base forms, other cases such as talon (genitive), taloja (partitive plural), and taloilla (inessive) are formed through inflection. Some nouns exhibit stem changes in inflection, but the perusmuoto remains the reference form.

For adjectives, the perusmuoto is the nominative singular form, used as the lemma to which inflectional endings are attached for degree, comparison, and other forms. Examples are keltainen (yellow) or iso (big). Adjectives agree with the noun they modify, but the perusmuoto remains the entry form from which all forms are derived.

For verbs, the perusmuoto is typically the present active infinitive, such as kirjoittaa (to write) or syödä (to eat). This form functions as the lemma in dictionaries and is the starting point for conjugation into tenses, moods, voices, and persons. Some verbs may have irregularities, but the infinitive perusmuoto is still the standard reference form.

In lexicography and language technology, perusmuoto serves as the primary entry form for analysis and lookup. Morphological analysis and part-of-speech tagging often rely on identifying the word’s perusmuoto to generate or recognize all inflected forms.