Latin word vulgare comes from Latvian *welh₂, and later Latin vulgaris (Common, usual, commonly known. Simple, plain.)
*welh₂ (Latvian)
*wel (Proto-Indo-European)
to wish, desire, want
vulgus (Latin)
(uncountable) the common people. (uncountable) the public. Gathering. Throng, crowd.
vulgaris (Latin)
Common, usual, commonly known. Simple, plain.
vulgare (Latin)
(proscribed) commonly, usually, popularly, vulgarly.