Illä

illä is the plural adessive suffix in Finnish grammar, used to mark location or means with plural nouns and pronouns. It corresponds to the singular adessive -lla/-llä and is attached to the stem to indicate “on/at” something or “with” something in plural. The form -illa/-illä varies with vowel harmony, but both spellings are common in everyday use.

In practice, -illä is added to nouns to express where something is located or the instrument by which an action is performed when the subject is plural. Examples include pöydillä (on the tables), kynillä (with pens), and vanhemmilla autoilla (with older cars). The meaning often depends on the verb and context: pöydillä on kirjoja means “There are books on the tables,” while kirjoitan kynillä means “I write with pens.”

The suffix also appears with personal pronouns to indicate possession or association in the plural. For example, meillä on koira means “we have a dog” or “there is a dog at us,” and heillä on auto means “they have a car.” In these uses, meillä, teillä, heillä are formed by combining the pronoun with -llä.

Notes for learners include that Finnish locative suffixes, including -illä, can express both spatial location and the instrument or means of an action, with the exact nuance guided by the sentence context. Because -illä is a productive plural form, it appears across a wide range of nouns and pronouns.

See also: Finnish grammar, adessive case, locative constructions, comitative expressions.