A disreputable or contemptible person; a term of contempt and insult, often used for someone fat or slovenly.
Of uncertain origin, possibly combining fustian with lugs (rough lumps), or from fustian meaning bombastic/shabby combined with a derogatory suffix. First appears in English around the 1600s.
This insult was popular in 17th-century England, and it's a great example of how people created colorful slang by mashing together rude-sounding syllables until they had something that sounded appropriately insulting and memorable.
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