Where does “tarjouskirje” come from?

tarjouskirje (Finnish) comes from Finnish tarjous, from Finnish tarjota, from Finnish tarjo-, from Finnish -ntä, from Proto-Finnic -nta — Forms action nouns from verbs.

tarjouskirje (Finnish): offer letter a letter detailing an offer for something that is on sale

Definitions

offer letter a letter detailing an offer for something that is on sale

Ancestry of “tarjouskirje”, step by step

tarjouskirje traces back through two separate lines of ancestry.

via Finnish tarjous

Step	Language	Word	Meaning
1	Finnish	tarjous	offer, bid, tender
2	Finnish	tarjota	to offer; to treat; to serve
3	Finnish	tarjo-	—
4	Finnish	-ntä	Front vowel variant of -nta; API
5	Proto-Finnic	-nta	Forms action nouns from verbs

via Finnish kirje

Step	Language	Word	Meaning
1	Finnish	kirje	letter
2	Finnish	kirja	book; quire
3	Proto-Finnic	kirja	decoration, carving, pattern

Every word from Proto-Finnic -nta →Every word from Finnish -ntä →Every word from Finnish tarjo- →