Sexual touching; foreplay. The term often implies that the activity is not followed with sex. You can be sure there's a lot of heavy petting going on under those bleachers.

dated Social gatherings in which couples engaged in amorous kissing, caressing, and fondling. I was shocked to learn that my grandmother—one of the most prude, conservative women in my life—used to go around to petting parties back in the 1920s.