Where does “kosiomatka” come from?

kosiomatka (Finnish) comes from Finnish matka, from Proto-Finnic matka, from Proto-Uralic mëtka — passage.

Ancestry of “kosiomatka”, step by step

kosiomatka traces back through two separate lines of ancestry.

via Finnish matka

StepLanguageWordMeaning
1Finnishmatkatrip; journey; distance
2Proto-Finnicmatkaway, path; journey, trip; distance
3Proto-Uralicmëtkapassage

via Finnish kosia

StepLanguageWordMeaning
1Finnishkosiato propose to, pop the question
2Proto-Finnickosidakto propose
Every word from Proto-Uralic mëtka →Every word from Proto-Finnic matka →Every word from Finnish matka →