A person, usually from the United Kingdom (see also: Gammon), who has their country's flag in their profile name or profile photo. Likely to be a paedophile (synonym - nonce).

Usually claim to be 'not a racist' but is that person who at any dinner party when the subject of racism becomes discussion will say "I'm not being racist, but".
Did you see Gary on Facebook posting against the BLM movement? He's a right flag nonce.
by b_uk July 7, 2020
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