Trough \Trough\ (tr[o^]f), n. [OE. trough, trogh, AS. trog, troh; akin to D., G., & Icel. trog, Sw. tr[*a]g, Dan. trug; probably originally meaning, made of wood, and akin to E.

1. See Tree, and cf. Trug.]

1. A long, hollow vessel, generally for holding water or other liquid, especially one formed by excavating a log longitudinally on one side; a long tray; also, a wooden channel for conveying water, as to a mill wheel. [1913 Webster]

2. Any channel, receptacle, or depression, of a long and narrow shape; as, trough between two ridges, etc. [1913 Webster]

3. (Meteor.) The transverse section of a cyclonic area where the barometric pressure, neither rising nor falling, has reached its lowest point. [Webster 1913 Suppl.]

Trough gutter (Arch.), a rectangular or V-shaped gutter, usually hung below the eaves of a house.

Trough of the sea, the depression between two waves. [1913 Webster]

Source: The Collaborative International Dictionary of English v.0.48
 

234 Moby Thesaurus words for "trough": adit, aerospace, aerosphere, air hole, air pocket, airspace, alveolation, alveolus, amplitude, antinode, antrum, aqueduct, armpit, basin, billow, bore, bottom, bottom glade, bottoms, bowl, breakers, bump, burrow, canal, canalization, canalize, carve, cavity, ceiling, chamfer, channel, chisel, chop, choppiness, chopping sea, chute, comb, comber, concave, concavity, conduit, corrugate, course, crack, crater, crest, crimp, crosswind, crypt, cup, cut, dado, dale, de Broglie wave, dell, delve, depression, diffraction, dig, dig out, dike, dingle, dip, dirty water, ditch, dredge, drill, drive, duct, eagre, eaves trough, egress, electromagnetic radiation, electromagnetic wave, empty space, engrave, entrance, entrenchment, excavate, exit, favorable wind, flute, fog, fold, follicle, fosse, frequency, frequency band, frequency spectrum, front, funnel chest, furrow, gap, gash, gill, glen, goffer, gouge, gouge out, gravity wave, groove, ground swell, grove, grub, guide, guided wave, gully, gutter, ha-ha, head wind, heave, heavy sea, heavy swell, high-pressure area, hole, hollow, hollow shell, in phase, incise, ingress, interference, intervale, ionosphere, jetstream, kennel, lacuna, lift, light, longitudinal wave, lop, low-pressure area, lower, lunar rill, mechanical wave, mine, moat, node, out of phase, overcast, pass, passage, passageway, peak, penstock, pentrough, period, periodic wave, pit, pleat, plow, pocket, popple, punch bowl, quarry, rabbet, radio wave, ravine, ray, reinforcement, resonance, resonance frequency, riffle, rifle, ripple, rise, roll, roller, rough water, roughness, rut, sap, scend, scoop, scoop out, score, scrabble, scrape, scratch, sea, seismic wave, send, shell, shock wave, shoot, shovel, sink, sinus, slit, socket, sound wave, soup, space, spade, strath, stratosphere, streak, striate, substratosphere, sunk fence, surf, surface wave, surge, swell, tail wind, tidal bore, tidal wave, tide wave, transverse wave, trench, tropopause, troposphere, troughing, troughway, tsunami, tunnel, turbulence, undulation, vale, valley, visibility, visibility zero, vug, wadi, water wave, wave, wave equation, wave motion, wave number, wavelength, wavelet, way, white horses, whitecaps, wrinkle

Source: Moby Thesaurus II by Grady Ward, 1.0
 

trough

Source: WordNet (r) 2.0
 

Trough \Trough\, n. (Meteor.) The transverse section of a cyclonic area where the barometric pressure, neither rising nor falling, has reached its lowest point.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Trough \Trough\, n. [OE. trough, trogh, AS. trog, troh; akin to D., G., & Icel. trog, Sw. tr[*a]g, Dan. trug; probably originally meaning, made of wood, and akin to E. tree. ? &

1. See Tree, and cf. Trug.]

1. A long, hollow vessel, generally for holding water or other liquid, especially one formed by excavating a log longitudinally on one side; a long tray; also, a wooden channel for conveying water, as to a mill wheel.

2. Any channel, receptacle, or depression, of a long and narrow shape; as, trough between two ridges, etc.

Trough gutter (Arch.), a rectangular or V-shaped gutter, usually hung below the eaves of a house.

Trough of the sea, the depression between two waves.

Source: Webster's Revised Unabridged Dictionary (1913)