kasulikuks

Kasulikuks is the translative singular form of the Estonian adjective kasulik, meaning “useful.” It is used to express a change of state or role, roughly “to become useful” or “into a state of being useful.” The form appears with verbs of change, most commonly muutuma (to become) and saama (to become/receive), as well as with osutuma (to prove to be).

Examples illustrate its use in practice. Ta muutus kasulikuks inimeseks. (He became a useful person.) Töö osutus kasulikuks paljude jaoks. (The work proved useful for many.) Ta saab kasulikuks meeskonnaks. (He becomes a useful member of the team.) Projekt osutus kasulikuks paljude jaoks. (The project proved useful for many.)

Etymology and usage notes: kasulikuks is formed from the stem kasulik with the translative ending -uks/-eks, a grammatical marker that signals transformation into the stated quality. It is distinct from the adverb kasulikult, which means “usefully.” Kasulikuks often appears without a following noun, but it also co-occurs with a noun in the translative case (e.g., kasulikuks inimeseks, kasulikuks meeskonnaks) to describe becoming or turning into that role or state.

See also: kasulik (useful), kasulikkus (usefulness), kasulikum (more useful), kasulikkust (the noun form related to usefulness).