A term of contempt or insult for a foolish or despicable person; a scoundrel.
Possibly from 'gull' (a fool or dupe) with the intensifying suffix '-ion.' The exact origin is uncertain, but it appears in early modern English as a derogatory term.
Medieval and Renaissance English had dozens of creative insults—'gullion,' 'loggerhead,' 'measle'—suggesting people invested real creativity in name-calling before the internet!
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