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  1. To fit in; joining; a jumping movement from one foot to the other.
  2. ["boxed"]. A jump. Start in 5th; assume the right leg is in front. Jump up, bend the right leg to 45 degrees. Land on the right foot with the left leg slightly bent and the left foot in front of the right ankle. The feet fit closely together, like a lid on a box; hence the name. Usually repeated to the other side: jump off right foot onto the left and land with right foot in front of the left ankle. This movement is often done while turning and travelling. Source: Vance's Fantastic - BALLET DICTIONARY