lem(n = noun.artifact) lunar excursion module, lunar module - a spacecraft that carries astronauts from the command module to the surface of the moon and back;
is a kind of ballistic capsule, space vehicle, spacecraft

   A lunar excursion module, a spacecraft designed to transport people from a command module in orbit around the moon to the surface of the moon and back again. [WordNet 1.5]

lem, abbr. lunar excursion module.