Where does “kohvajää” come from?

kohvajää (Finnish) comes from Finnish jää, from Proto-Finnic jää, from Proto-Uralic jäŋe — ice.

Ancestry of “kohvajää”, step by step

kohvajää traces back through two separate lines of ancestry.

via Finnish jää

StepLanguageWordMeaning
1Finnishjääice; rock; in the expression on the rocks =...
2Proto-Finnicjääice
3Proto-Uralicjäŋeice

via Finnish kohva

StepLanguageWordMeaning
1Finnishkohvaporous ice formed from frozen slush; slush ice, snow ice
2Finnishkohma—
Every word from Proto-Uralic jäŋe →Every word from Proto-Finnic jää →Every word from Finnish jää →