n.1. A squared-off log or a large, oblong piece of timber, metal, or stone used especially as a horizontal support in construction.
2. Nautical a. A transverse structural member of a ship's frame, used to support a deck and to brace the sides against stress.
b. The breadth of a ship at the widest point.
c. The side of a ship: sighted land off the starboard beam.
3. Informal The widest part of a person's hips: broad in the beam.
4. A steel tube or wooden roller on which the warp is wound in a loom.
5. An oscillating lever connected to an engine piston rod and used to transmit power to the crankshaft.
6. a. The bar of a balance from which weighing pans are suspended.
b. Sports A balance beam.
7. The main horizontal bar on a plow to which the share, coulter, and handles are attached.
8. One of the main stems of a deer's antlers.
9. a. A ray or shaft of light.
b. A concentrated stream of particles or a similar propagation of waves: a beam of protons; a beam of light.
10. A radio beam.
v.tr.1. To emit or transmit: beam a message via satellite.
2. To express by means of a radiant smile: He beamed his approval of the new idea.