Synonyms for Bastard (same or very similar meaning)
WordNet sense 1 (the illegitimate offspring of unmarried parents):
illegitimate, by-blow, whoreson, illegitimate child
WordNet sense 2 (insulting terms of address for people who are stupid or irritating or ridiculous):
cocksucker, motherfucker, prick, shit, dickhead, asshole, mother fucker, son of a bitch
WordNet sense 3 (derogatory term for a variation that is not genuine; something irregular or inferior or of dubious origin):
mongrel
WordNet sense 4 (fraudulent; having a misleading appearance):
bogus, fake, phoney, phony
WordNet sense 5 (not genuine; imitating something superior):
counterfeit, imitative
From the ODE community, based on WordNet
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