bet /bet/ verb [I, T] (present participle betting, past tense and past participle bet)
› to risk money on the result of a game, competition, etc: He lost all his money betting on horses. [+ two objects + (that)] I bet him a dollar that I was right. I bet informal › something that you say to show that you believe that something is true or will happen: [+ (that)] I bet that he's forgotten my birthday again.
You bet! mainly US informal › used to say that you will do something with enthusiasm: "Are you going to Pam's party?" "You bet!"