tarkkaavaiseen
Tarkkaavaiseen is a Finnish inflected form of the adjective tarkkaavainen, which means attentive or vigilant. It is not a separate lexical entry, but a case form that can appear when the adjective is used within a grammatical structure requiring a case ending. Specifically, tarkkaavaiseen is the illative singular form of tarkkaavainen, used in contexts where the clause or phrase expresses motion toward or into something described by the adjective. The corresponding genitive singular form of the adjective is tarkkaavaisen.
In Finnish, adjectives decline for case, number, and, to some extent, definiteness. When an adjective is used
Etymology and morphology: tarkkaavainen is formed from tarkka- (careful, precise) with the suffix -ainen to create
See also: tarkkaavainen, Finnish grammar, adjectives as nouns.
References: Finnish language grammar resources on case endings and adjective inflection.