To stake or pledge upon the outcome of an event; to wager.
To be sure of something; to be able to count on something.
Fancy going for a drink after work? You bet I do!
To place money into the pot in order to require others do the same, usually only used for the first person to place money in the pot on each round.
The act of placing a bet.
Describing one who bets or gambles.
If I were a betting man, I'd wager my next pay check he couldn't do that again.