I think it's an American euphemism for swearing instead of saying 'shit'
like we sometimes say sugar (not me, obviously, but you know what I mean).
Joy says it all the time in My Name is Earl.
(
Afinkawan Yes I can hear you Clem Fandango,
Wed 23 Apr 2008, 13:31,
archived)
yes, I've noticed that
*grumbles about americanisms*
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drbroon abloooobloobloo,
Wed 23 Apr 2008, 13:33,
archived)