The Collaborative International Dictionary of English v.0.48:
leg-pull \leg-pull\ n. An attempt to make somebody believe something that is not true, done as a joke. Syn: leg-pulling. [WordNet 1.5]WordNet (r) 3.0 (2006):
leg-pull n 1: as a joke: trying to make somebody believe something that is not true [syn: leg-pull, leg-pulling]