Sumuuntuvat

Sumuuntuvat is a Finnish verb form that means "they fog up" or "become foggy/cloudy." It is the present tense, third-person plural form of the verb sumuuntua, which describes a change of state when something gains foggy or unclear surface. The term is commonly used for physical surfaces such as windows, windshields, eyeglasses, or camera lenses that accumulate moisture or condensation.

Etymology and grammar: sumuuntua is built from sumu, meaning fog or mist, with the state-changing suffix -untua. The form sumuuntuvat corresponds to a plural subject in the present indicative, as in "ikkunat sumuuntuvat" (the windows fog up). The singular present form is sumuuntuu, used with a single surface or sense of fogging.

Usage and contexts: In everyday language, sumuuntuvat describes condensation or humidity effects that reduce transparency, typically due to temperature differences, humidity, or breath. It is also used metaphorically to indicate that thoughts, memories, or judgments are becoming unclear or obscured. While commonly applied to tangible surfaces, it can appear in literary or descriptive writing to convey mood or atmosphere.

Examples: Ikkunat sumuuntuvat aamulla pakkasen ja lämmön erosta. Linssit sumuuntuvat kun kamera siirtyy kylmästä lämpimään. Mieli sumuuntuu kiireisen päivän jälkeen.

See also: sumuuntua, sumuuntuminen, sumu, condensation terminology in Finnish.