leapfrog

thumb|Children playing leapfrog in Pieter Bruegel the Elder|Bruegel's ''Children's Games'' thumb|A game of leapfrog at a girls' school in Mussoorie, India

Leapfrog is a children's game of physical movement of the body in which players vault over each other's stooped backs. The term has also become a verb describing any situation in which a person or entity at the rear of a line advances directly to the front.