Where does “yöasu” come from?

yöasu (Finnish) comes from Finnish asu, from Finnish -u, from Proto-Finnic -u.

yöasu (Finnish): nightclothes

Definitions

Step	Language	Word	Meaning
1	Finnish	asu	attire, dress, suit, raiment; form, figure,...
2	Finnish	-u	Forms nouns from verbs. Most common with "e"- and...
3	Proto-Finnic	-u	—

yöasu — Etymology, Origin & Word History | Etymology Explorer