What is Live One?
1.
A lively, or interesting or annoying or peculiar or uncontrollable etc etc person
Also someone or something likely to win in a game, race etc.
"Looks like we've got ourselves a live one"
"I've bet on a real live one"
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2.
In poker, a bad player at the table. Good players rely on live ones to play too many hands, and thus give away their money by making mistakes.
Almost anyone would be a live one in the high stakes poker games in Vegas since they would get outplayed by the top professionals.
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