| 1. | any of various relatively long pieces of metal, wood, stone, etc., manufactured or shaped esp. for use as rigid members or parts of structures or machines. |
| 2. | Building Trades. a horizontal bearing member, as a joist or lintel. |
| 3. | Engineering. a rigid member or structure supported at each end, subject to bending stresses from a direction perpendicular to its length. |
| 4. | Nautical.
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| 5. | Aeronautics. the direction perpendicular to the plane of symmetry of an aircraft and outward from the side. |
| 6. | the widest part. |
| 7. | Slang. the measure across both hips or buttocks: broad in the beam. |
| 8. | Machinery.
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| 9. | the crossbar of a balance, from the ends of which the scales or pans are suspended. |
| 10. | a ray of light: The sun shed its beams upon the vineyard. |
| 11. | a group of nearly parallel rays. |
| 12. | Radio, Aeronautics. a signal transmitted along a narrow course, used to guide pilots through darkness, bad weather, etc. |
| 13. | Electronics. a narrow stream of electrons, as that emitted from the electron gun of a cathode ray tube. |
| 14. | the angle at which a microphone or loudspeaker functions best. |
| 15. | the cone-shaped range of effective use of a microphone or loudspeaker. |
| 16. | Citizens Band Radio Slang. beam antenna. |
| 17. | a gleam; suggestion: a beam of hope. |
| 18. | a radiant smile. |
| 19. | the principal stem of the antler of a deer. |
| 20. | to emit in or as in beams or rays. |
| 21. | Radio. to transmit (a signal) in a particular direction. |
| 22. | Radio and Television. to direct (a program, commercial message, etc.) to a predetermined audience. |
| 23. | to emit beams, as of light. |
| 24. | to smile radiantly or happily. |
| 25. | beam in, Citizens Band Radio Slang. to be received under optimum conditions; be heard loud and clear: They told me I was really beaming in. |
| 26. | fly the beam, Radio, Aeronautics. (of an aircraft) to be guided by a beam. |
| 27. | off the beam,
|
| 28. | on the beam,
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(I-)beam
[ˈ(ɑɪ)bim]
|
off the beam
Off course, on the wrong track, as in He's way off the beam with that argument. This colloquial term and its antonym, on the beam, meaning "on the right track," allude to directing aircraft by means of radio beams. [Colloquial; mid-1900s]