I'd ___ my life on it (3)
I believe the answer is:
bet
(Other definitions for bet that I've seen before include "Wager, back" , "Speculation" , "22 across will accept one" , "'Stake, wager (3)'" , "Wager, or the sum waged" .)
I believe the answer is:
bet
(Other definitions for bet that I've seen before include "Wager, back" , "Speculation" , "22 across will accept one" , "'Stake, wager (3)'" , "Wager, or the sum waged" .)