Definition: Allows you to link together two or more individual bets, similar to a parlay. However, unlike a parlay, it is not an all or nothing bet. You are basically instructing the sportsbook that "if" the first bet wins, then place a second bet on this other proposition.
If your first bet wins, the sportsbook will place your second bet. If your first bet loses, there will be no second bet. This type of bet is primarily used as a form of money management.
What can be initially confusing is the fact that the starting times of the games bet on is irrelevant. You can place a two team "if bet" in which a game at 5:00 p.m. is your first bet, and if you win that game, your second bet is a game already played early in the day.
Example: Jackson placed a two team "if bet" on the Raiders NFL football game and the Seahawks football game. He bet $20 on the Raiders game. If he wins that bet, the sportsbook will place a $40 bet for him on the Seahawks game.
Pregame.com offers the Sports Gambling Glossary to give you a better understanding of sports betting terms and definitions so you can bet with confidence.