päiväänsä

Päivänsä is a Finnish grammatical form derived from the noun päivä (day). It is created by taking the genitive form päivän and adding the third-person possessive suffix sä, resulting in päivänsä. The meaning is "his day" or "her day," indicating ownership of the day by a third-person subject.

In usage, päivänsä functions as a bound possessive noun phrase. It does not stand alone as a free noun; instead, it occurs within sentences where the day is attributed to someone or something. The form showcases Finnish’s tendency to express possession through suffixes rather than separate possessive pronouns.

A typical example is Se on hänen päivänsä, which can be translated as "It is his day" or, depending on context, "That is his turn." Another example is Hänellä on päivänsä koittaa in a figurative sense, meaning "His day is coming" or "The time for him has arrived." Context often clarifies whether the phrase is literal (a specific day belonging to someone) or metaphorical (a moment of opportunity for that person).

Etymologically, päivää means day, the genitive suffix -n marks possession, and the third-person possessive suffix -sä completes the form to express ownership by he, she, or it. Päivänsä thus exemplifies how Finnish builds possessive noun phrases by combining stem, genitive, and person suffixes.

See also: Finnish grammar, possessive suffixes, genitive case, noun phrases.