Where does “vomire” come from?

vomire (Vulgar Latin) comes from Latin vomō, from Proto-Indo-European wemh₁- — to spew, to vomit.

Ancestry of “vomire”, step by step

Step	Language	Word	Meaning
1	Latin	vomō	to be sick; to vomit, puke, throw up; discharge
2	Proto-Indo-European	wemh₁-	to spew, to vomit