niin

Niin is a common Finnish word with several grammatical functions. It is most often used as an adverb meaning “so,” “thus,” or “that” to intensify an adjective or to mark a degree. It can also function as a conjunction in phrases that link clauses, and as a discourse particle that helps structure conversation. In Finnish, niin is etymologically related to cognate words in other Finnic languages, such as Estonian nii, both conveying the idea of degree or emphasis.

As a degree adverb, niin precedes adjectives or adverbs to express emphasis: for example, “se on niin hyvä” (it is so good) and “minä olen niin väsynyt” (I am so tired). It can pair with quantities or intensifiers, as in “niin paljon” (so much) or “niin paljon kuin” (as much as). It is also used in negative constructions like “en ole niin varma” (I’m not that sure).

As a conjunction, niin appears in clauses to indicate result or consequence, most often in sentences like “Hän oli niin väsynyt, että nukahti” (He was so tired that he fell asleep). It can also appear in comparisons with phrases such as “niin kuin,” meaning “as” or “like,” e.g., “Hän pukeutuu niin kuin ammattilainen” (He dresses like a professional).

As a discourse marker, niin can serve to acknowledge a previous statement or invite continuation, and the interjection “Niin?” is a common way to signal interest or prompt a response, roughly translating to “Really?” or “Is that so?”

In addition to the Finnish usage, NIIN in all caps is an acronym in logistics for National Item Identification Number, used by defense and supply systems to identify items.