Where does “puristemehu” come from?

puristemehu (Finnish) comes from Finnish mehu, from Finnish -u, from Proto-Finnic -u — Forms nouns from adjectives, nouns.

puristemehu (Finnish): must pressed fruit juice that will ferment or has fermented, usually from grapes

Definitions

must pressed fruit juice that will ferment or has fermented, usually from grapes

puristemehu traces back through two separate lines of ancestry.

Step	Language	Word	Meaning
1	Finnish	mehu	juice; cordial
2	Finnish	-u	Forms nouns from verbs. Most common with "e"- and...
3	Proto-Finnic	-u	Forms nouns from adjectives, nouns

Step	Language	Word	Meaning
1	Finnish	puriste	briquet
2	Finnish	puristaa	to press; to clasp, grasp, grip, squeeze, shake,...
3	Finnish	purista	to make a quiet purring sound; to talk quietly or...