Synonyms for Vulgar (same or very similar meaning)
WordNet sense 1 (lacking refinement or cultivation or taste):
coarse, common, uncouth, rough-cut
WordNet sense 2 ((used of persons and their behavior) not refined; uncouth):
unrefined
WordNet sense 3 (of or associated with the great masses of people):
plebeian, unwashed
WordNet sense 4 (of humble birth or origins):
lowborn
WordNet sense 5 (being or characteristic of or appropriate to everyday language):
vernacular
WordNet sense 6 (used of spoken and written language):
informal
WordNet sense 7 (conspicuously and tastelessly indecent):
crude, earthy, gross
WordNet sense 8 (offensive to good taste especially in sexual matters):
indecent
From the ODE community, based on WordNet
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