sisïön

Sisään is a Finnish adverbial postposition that indicates motion into the interior of a space or object. It is used with verbs of movement to express entering or going inside, and it often translates as into or inside in English. It functions to mark direction toward the interior rather than a static location.

In usage, sisään is commonly found in phrases such as mennään sisään (let's go inside), tule sisään (come in), or hän astui sisään taloon (he/she stepped into the house). It answers questions about movement toward an interior space, for example where someone is going or entering. It contrasts with sisällä, which denotes a state of being inside a location rather than the act of entering.

The word can appear on signage to indicate an entrance, for instance a door sign reading Sisään meaning Entrance. It also participates in compound terms related to entry, such as sisäänkäynti (entrance).

Etymologically, sisään emerges from the adjective sisä meaning inner, combined with a directional postposition form that marks motion toward the interior. This distinguishes it from other interior-related forms like sisällä (inside, in) which describe location rather than movement.