Leapfrog is a children's game in which players vault over each other's stooped backs. The first participant rests hands on knees and bends over, this is called giving a back.

The next player places hands on the first's back and leaps over by straddling legs wide apart on each side. On landing he stoops down and a third leaps over the first and second, and the fourth over all others successively, etcetera; the number of particpants is not fixed.