1.  Any large piece of timber or iron long in proportion to its thickness, and prepared for use. [1913 Webster]

2.  One of the principal horizontal timbers of a building or ship. [1913 Webster]
"The beams of a vessel are strong pieces of timber stretching across from side to side to support the decks." [1913 Webster]

3.  The width of a vessel; as, one vessel is said to have more beam than another. [1913 Webster]

4.  The bar of a balance, from the ends of which the scales are suspended. [1913 Webster]
"The doubtful beam long nods from side to side." [1913 Webster]

5.  The principal stem or horn of a stag or other deer, which bears the antlers, or branches. [1913 Webster]

6.  The pole of a carriage. Dryden. [1913 Webster]

7.  A cylinder of wood, making part of a loom, on which weavers wind the warp before weaving; also, the cylinder on which the cloth is rolled, as it is woven; one being called the fore beam, the other the back beam. [1913 Webster]

8.  The straight part or shank of an anchor. [1913 Webster]

9.  The main part of a plow, to which the handles and colter are secured, and to the end of which are attached the oxen or horses that draw it. [1913 Webster]

10.  A heavy iron lever having an oscillating motion on a central axis, one end of which is connected with the piston rod from which it receives motion, and the other with the crank of the wheel shaft; -- called also working beam or walking beam. [1913 Webster]

11.  A ray or collection of parallel rays emitted from the sun or other luminous body; as, a beam of light, or of heat. [1913 Webster]
"How far that little candle throws his beams!" [1913 Webster]

12.  A ray; a gleam; as, a beam of comfort. [1913 Webster]
"Mercy with her genial beam." [1913 Webster]

13.  One of the long feathers in the wing of a hawk; -- called also beam feather. [1913 Webster]

   To send forth; to emit; -- followed ordinarily by forth; as, to beam forth light. [1913 Webster]

   To emit beams of light. [1913 Webster]
"He beamed, the daystar of the rising age." [1913 Webster]

beam, n. & v.
--n.
1 a long sturdy piece of squared timber or metal spanning an opening or room, usu. to support the structure above.
2 a a ray or shaft of light. b a directional flow of particles or radiation.
3 a bright look or smile.
4 a a series of radio or radar signals as a guide to a ship or aircraft. b the course indicated by this (off beam).
5 the crossbar of a balance.
6 a a ship's breadth at its widest point. b the width of a person's hips (esp. broad in the beam).
7 (in pl.) the horizontal cross-timbers of a ship supporting the deck and joining the sides.
8 the side of a ship (land on the port beam).
9 the chief timber of a plough.
10 the cylinder in a loom on which the warp or cloth is wound.
11 the main stem of a stag's antlers.
12 the lever in an engine connecting the piston-rod and crank.
13 the shank of an anchor.
--v.
1 tr. emit or direct (light, radio waves, etc.).
2 intr. a shine. b look or smile radiantly.

Idiom:
beam-compass (or -compasses) compasses with a beam connecting sliding sockets, used for large circles. a beam in one's eye a fault that is greater in oneself than in the person one is finding fault with (see Matt. 7:3). off beam colloq. mistaken. on the beam colloq. on the right track. on the beam-ends (of a ship) on its side; almost capsizing. on one's beam-ends near the end of one's resources.

Etymology:
OE beam tree f. WG

VB  be beautiful, shine, beam, bloom, become one, set off, grace, render beautiful, beautify, polish, burnish, gild, set out, snatch a grace beyond the reach of art.

N  support, ground, foundation, base, basis, terra firma, bearing, fulcrum, bait, caudex crib, point d'appui, pou sto, purchase footing, hold, locus standi, landing place, landing stage, stage, platform, block, rest, resting place, groundwork, substratum, riprap, sustentation, subvention, floor, supporter, aid, prop, stand, anvil, fulciment, cue rest, jigger, monkey, stay, shore, skid, rib, truss, bandage, sleeper, stirrup, stilts, shoe, sole, heel, splint, lap, bar, rod, boom, sprit, outrigger, ratlings, staff, stick, crutch, alpenstock, baton, staddle, bourdon, cowlstaff, lathi, mahlstick, post, pillar, shaft, thill, column, pilaster, pediment, pedicle, pedestal, plinth, shank, leg, socle, zocle, buttress, jamb, mullion, abutment, baluster, banister, stanchion, balustrade, headstone, upright, door post, jamb, door jamb, frame, framework, scaffold, skeleton, beam, rafter, girder, lintel, joist, travis, trave, corner stone, summer, transom, rung, round, step, sill, angle rafter, hip rafter, cantilever, modillion, crown post, king post, vertebra, columella, backbone, keystone, axle, axletree, axis, arch, mainstay, trunnion, pivot, rowlock, peg, tiebeam, thole pin, board, ledge, shelf, hob, bracket, trevet, trivet, arbor, rack, mantel, mantle piece, mantleshelf, slab, console, counter, dresser, flange, corbel, table, trestle, shoulder, perch, horse, easel, desk, clotheshorse, hatrack, retable, teapoy, seat, throne, dais, divan, musnud, chair, bench, form, stool, sofa, settee, stall, arm chair, easy chair, elbow chair, rocking chair, couch, fauteuil, woolsack, ottoman, settle, squab, bench, aparejo, faldstool, horn, long chair, long sleeve chair, morris chair, lamba chauki, lamba kursi, saddle, pannel, pillion, side saddle, pack saddle, pommel, bed, berth, pallet, tester, crib, cot, hammock, shakedown, trucklebed, cradle, litter, stretcher, bedstead, four poster, French bed, bunk, kip, palang, bedding, bichhona, mattress, paillasse, pillow, bolster, mat, rug, cushion, footstool, hassock, tabouret, tripod, monopod, Atlas, Persides, Atlantes, Caryatides, Hercules, supporting, supported, fundamental, dorsigerous, astride on, straddle.

N  laterality, side, flank, quarter, lee, hand, cheek, jowl, jole, wing, profile, temple, parietes, loin, haunch, hip, beam, gable, gable end, broadside, lee side, points of the compass, East, Orient, Levant, West, orientation, lateral, sidelong, collateral, parietal, flanking, skirting, flanked, sideling, many sided, multilateral, bilateral, trilateral, quadrilateral, Eastern, orient, oriental, Levantine, Western, occidental, Hesperian, sideways, sidelong, broadside on, on one side, abreast, alongside, beside, aside, by the side of, side by side, cheek by jowl, to windward, to leeward, laterally, right and left, on her beam ends, his cheek the may of days outworn.

N  gravity, gravitation, weight, heaviness, specific gravity, pondorosity, pressure, load, burden, burthen, ballast, counterpoise, lump of, mass of, weight of, lead, millstone, mountain, Ossa on Pelion, weighing, ponderation, trutination, weights, avoirdupois weight, troy weight, apothecaries' weight, grain, scruple, drachma, ounce, pound, lb, arroba, load, stone, hundredweight, cwt, ton, long ton, metric ton, quintal, carat, pennyweight, tod, gram, centigram, milligram, microgram, kilogram, nanogram, picogram, femtogram, attogram, balance, scale, scales, steelyard, beam, weighbridge, spring balance, piezoelectric balance, analytical balance, two-pan balance, one-pan balance, postal scale, baby scale, statics, weighty, weighing, heavy as lead, ponderous, ponderable, lumpish, lumpy, cumbersome, burdensome, cumbrous, unwieldy, massive, incumbent, superincumbent.

N  light, ray, beam, stream, gleam, streak, pencil, sunbeam, moonbeam, aurora, day, sunshine, light of day, light of heaven, moonlight, starlight, sunlight, daylight, broad daylight, noontide light, noontide, noonday, noonday sun, glow, glimmering, glint, play of light, flood of light, phosphorescence, lambent flame, flush, halo, glory, nimbus, aureola, spark, scintilla, facula, sparkling, emication, scintillation, flash, blaze, coruscation, fulguration, flame, lightning, levin, ignis fatuus, luster, sheen, shimmer, reflexion, reflection, gloss, tinsel, spangle, brightness, brilliancy, splendor, effulgence, refulgence, fulgor, fulgidity, dazzlement, resplendence, transplendency, luminousness, luminosity, lucidity, renitency, nitency, radiance, radiation, irradiation, illumination, actinic rays, actinism, Roentgen-ray, Xray, photography, heliography, photometer, optics, photology, photometry, dioptrics, catoptrics, chiaroscuro, clairobscur, clear obscure, breadth, light and shade, black and white, tonality, reflection, refraction, dispersion, refractivity, shining, luminous, luminiferous, lucid, lucent, luculent, lucific, luciferous, light, lightsome, bright, vivid, splendent, nitid, lustrous, shiny, beamy, scintillant, radiant, lambent, sheen, sheeny, glossy, burnished, glassy, sunny, orient, meridian, noonday, tide, cloudless, clear, unclouded, unobscured, gairish, garish, resplendent, transplendent, refulgent, effulgent, fulgid, fulgent, relucent, splendid, blazing, in a blaze, ablaze, rutilant, meteoric, phosphorescent, aglow, bright as silver, light as day, bright as day, light as noonday, bright as noonday, bright as the sun at noonday, actinic, photogenic, graphic, heliographic, heliophagous, a day for gods to stoop and men to soar, dark with excessive bright.

VB  shine, glow, glitter, glister, glisten, twinkle, gleam, flare, flare up, glare, beam, shimmer, glimmer, flicker, sparkle, scintillate, coruscate, flash, blaze, be bright, reflect light, daze, dazzle, bedazzle, radiate, shoot out beams, fulgurate, clear up, brighten, lighten, enlighten, levin, light, light up, irradiate, shine upon, give out a light, hang out a light, cast light upon, cast light in, throw light upon, throw light in, shed light upon, shed luster upon, illume, illumine, illuminate, relume, strike a light, kindle.

balance beam, beam balance, beam of light, beam scale, beam tree, box beam, electron beam, high beam, inoic beam, ion beam, laser beam, light beam, low beam, on the beam, particle beam, radio beam, tie beam