Pyörivään

Pyörivän is the genitive singular form of the Finnish adjective pyörivä, meaning rotating or spinning. In Finnish grammar, pyörivä is a present active participle used as an adjective, and pyörivän is its genitive singular form, beginning to be used when the noun it modifies is in the genitive case. Thus pyörivän appears in noun phrases such as pyörivän kappaleen, pyörivän koneen, or pyörivän järjestelmän, roughly translating to “of the rotating piece,” “of the rotating machine,” or “of the rotating system.”

The form agrees with the noun in number and case. When the noun is in another case, the adjective takes the corresponding form. For example, in partitive constructions you would encounter pyörivää, as in pyörivää kappaletta (a rotating piece, partitive). In compound descriptions common in technical and scientific Finnish, pyörivän is used to express possession or relation to the noun, as in pyörivän järjestelmän vakaus (the stability of the rotating system) or pyörivän koneen hihna (the belt of the rotating machine).

Etymology and syntax: pyörivä derives from the verb pyöriä, meaning to rotate, with the present participle suffix -vä. The genitive singular ending -n marks the form used when modifying a genitive noun. Pyörivä/pyörivän forms are common in descriptive language for machinery, physics, and engineering contexts where a noun’s rotating state is a key attribute. See also Finnish grammar, adjectives, and present active participles.