Where does “vulgatio” come from?

vulgatio (Latin) comes from Latin vulgo, from Latin vulgus, from Proto-Indo-European wel — to throng, crowd; to wish, desire, want.

Ancestry of “vulgatio”, step by step

Step	Language	Word	Meaning
1	Latin	vulgo	I broadcast, publish, divulge, issue, make known...
2	Latin	vulgus	the common people; the public; throng, crowd
3	Proto-Indo-European	wel	to throng, crowd; to wish, desire, want

vulgatio — Etymology, Origin & Word History | Etymology Explorer