A burner is something designed to create flames or heat, like the circular heating elements on top of a stove where you place pots and pans. When you turn the dial, gas flows through the burner and ignites, or an electric coil heats up red hot. A gas grill has burners underneath the grates. The furnace in a basement has a burner that heats air for the whole house.

The word also describes a cheap, disposable cell phone that people buy temporarily and throw away after using. These “burner phones” don't require contracts or personal information, so someone might use one while traveling abroad to avoid expensive roaming charges, or to keep their main number private. In spy stories, characters often use burner phones so their calls can't be traced back to them.

In slang, calling someone a burner can mean they're exceptionally talented or impressive at something, like “That pitcher is a real burner!” The phrase on the back burner means something has been postponed or set aside temporarily, like when your mom puts her book club plans on the back burner during a busy month at work, the same way you'd move a pot of soup to a back burner to keep it warm without letting it boil over.