POPSUGAR Food Leavener Leavener Definition: Leavener by Food 7/02/07 4 Shares Like us on Facebook Leavener Leaveners (or leavening agents) are substances used to produce air bubbles that cause baked goods to rise. Baking powder, baking soda and yeast are the most common forms of leaveners. Read More LeavenerYeastBaking PowderBaking SodaDefinitions Get inspired with our daily newsletter Love and Sex Home DIY Tech Vegetarian Food Sign up with By signing up, I agree to the Terms and to receive emails from POPSUGAR. poetess 7 years Baking soda works miracles. crispet1 7 years Ok good, I knew that!