I/I'll bet(redirected from I'll Bet)
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I/I’ll ˈbet (that...)(informal)
1 I am certain (that...): I bet he’ll be late for the meeting — he always is.
2 used to show that you agree with somebody or are not surprised to hear something: ‘I’m furious about what she said to me.’ ‘I bet (you are)!’
See also: bet