you bet your bottom

you bet your bottom

You can be sure that something will happen. A less vulgar alternative to "you can bet your ass." I just know Sally will get the lead in the school play—you can bet your bottom!
See also: bet, bottom
References in classic literature ?
and you bet your bottom dollar, Johnny, it AIN'T just as easy as it is for a cat to have twins
Would you bet your bottom dollar everyone will come out smelling of roses?