hetkittäisten

Hetkittäisten is a Finnish term used primarily in technical or scholarly contexts to refer to entities or quantities related to moments or instantaneous states. The base adjective hetkittäinen means “instantaneous” or “momentary,” formed with the common Finnish suffix -inen. When used as a noun phrase, adjectives are inflected like other Finnish adjectives, and the genitive plural form is hetkittäisten, for example in phrases such as hetkittäisten suureiden arvojen muutokset, referring to changes in instantaneous quantities.

In practice, hetkittäisten appears most often in physics, mathematics, and philosophy where there is a need to distinguish properties that hold at a single moment from those describing longer intervals or continuous evolution. The term can also appear in discussions of time and presents notions, such as momentary states of systems or events, to emphasize their instantaneous character. Because hetkittäisten is specialized, it is relatively rare outside academic or technical writing; in everyday Finnish, speakers more commonly use forms like hetkellinen or describe instantaneous values with phrases such as hetkellinen nopeus or hetkellinen arvo.

Etymology and related forms: hetkittäinen is built from hetki (moment) with the -täinen suffix that yields an adjective meaning “instantaneous.” The genitive plural form hetkittäisten follows standard Finnish adjective inflection when the adjective-modified noun is treated as a plural entity in the genitive.

See also: hetkellinen, instantaneous in physics and mathematics, presentism.