na-adjective, noun
Describes language, behavior, or taste that is crude, unrefined, or lacking in sophistication. Often used for speech or manners.
彼の卑俗な冗談にはうんざりだ。
I'm fed up with his vulgar jokes.
あの番組は卑俗すぎて見るに耐えない。
That show is too coarse to watch.
下品 is more common and directly means 'vulgar, crude' in everyday contexts. 卑俗 is slightly more formal and emphasizes lack of refinement or sophistication.
低俗 also means 'vulgar, lowbrow' but often refers to mass media or entertainment that appeals to base instincts. 卑俗 can apply to personal behavior or language as well.
Compound of 卑 (base, lowly) and 俗 (customs, vulgar). The exact historical derivation is uncertain; the spelling is conventionally associated with the meaning 'vulgar, coarse'.