Where does “rapsaus” come from?

rapsaus (Finnish) comes from Finnish räpsähtää, from Finnish -ähtää, from Proto-Finnic -ahtadak, from Proto-Uralic -ašta-.

Ancestry of “rapsaus”, step by step

StepLanguageWordMeaning
1Finnishräpsähtääto blink
2Finnish-ähtääFront vowel variant of -ahtaa
3Proto-Finnic-ahtadakForms momentane verbs
4Proto-Uralic-ašta-—
Every word from Proto-Uralic -ašta- →Every word from Finnish -ähtää →Every word from Finnish räpsähtää →