ympyräisen
Ympyräisen is the genitive singular form of the Finnish adjective ympyräinen, meaning circular or round. It is used when the adjective modifies a noun that is in the genitive case. For example, in the phrase ympyräisen talon katto, the noun talo is in genitive (talon) and ympyräisen serves as the descriptive modifier in genitive form, yielding “the roof of the circular house” or “the circular house’s roof.”
In Finnish, adjectives ending in -inen decline like other -inen adjectives. Common forms include: nominative singular
Etymology traces ympyräinen to ympyrä (circle) plus the adjectival suffix -inen, a productive combination in Finnish
Usage notes: ympyräisen is not a standalone noun but a declined adjective form. It is most common