äillä

öillä is a Finnish linguistic term referring to the plural adessive form of the noun ö, a loanword from Swedish meaning "island." In Finnish grammar, the adessive case marks location or position on something, and the plural form -illä is used when the reference is to multiple islands. Thus, öillä literally means "on the islands" and is used to describe location or distribution across several islands in a geographic context.

Etymology and form are tied to the broader pattern of Finnish handling of foreign loanwords in inflection. The base word ö, borrowed from Swedish, functions like a short noun meaning "island," and the suffix -illä is the standard plural adessive ending for many Finnish nouns. The combination reflects how Finnish encodes spatial information about multiple landmasses within a single word.

Usage and frequency are limited. Öillä appears mainly in geographic, historical, or descriptive texts dealing with archipelagos or island groups. In everyday Finnish, speakers more commonly use Saarilla or refer to specific islands by name. When it does appear, it is typically in contexts that enumerate or compare multiple islands, or in descriptions of where activities or features occur.

See also: Finnish grammar, inflection, adessive case, loanwords in Finnish, archipelago terminology.