A coward / liar. Someone who comes up with poor excuses.

Comes from Durham England. Derives from the 1569 Rebellion when Sir George Bowes refused to leave Barnard Castle to engage in battle.
"Kevin reckons he's not allowed to go out on the lash tonight because of his knee. That's a bit barney castle."
by KittenJuggler May 26, 2020
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