bet

all bets are off the outcome of a particular situation is unpredictable. informal

don't bet on it used to express doubt about an assertion or situation. informal

you bet you may be absolutely certain. informal

2010Manchester Music Would people still come? You bet: sold out in advance, but then it is one hell of a line-up.

you can bet your boots (or bottom dollar or life) you may be absolutely certain. informal

bet the farm risk everything that you own on a bet, investment, or enterprise. North American informal

hedge your bets: seehedge.

a safe bet a certainty.

☞ A safe bet originally referred to a horse that was confidently expected to win a race.

2002Observer It is a safe bet that as the Western world gets fatter, the people on its television screens will continue to get thinner.