The Collaborative International Dictionary of English v.0.48:

Gulch \Gulch\, n.
   1. Act of gulching or gulping. [Obs.]
      [1913 Webster]

   2. A glutton. [Obs.] --B. Jonson.
      [1913 Webster]

   3. A ravine, or part of the deep bed of a torrent when dry; a
      gully.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Gulch \Gulch\, v. t. [OE. gulchen; cf. dial. Sw. g["o]lka to
   gulch, D. gulzig greedy, or E. gulp.]
   To swallow greedily; to gulp down. [Obs.]
   [1913 Webster]

WordNet (r) 3.0 (2006):

gulch
    n 1: a narrow gorge with a stream running through it [syn:
         gulch, flume]

Moby Thesaurus II by Grady Ward, 1.0:

100 Moby Thesaurus words for "gulch":
   abysm, abyss, aqueduct, arroyo, bed, box canyon, breach, break,
   canal, canyon, cavity, chap, chasm, check, chimney, chink, cleft,
   cleuch, clough, clove, col, coulee, couloir, crack, cranny,
   creek bed, crevasse, crevice, culvert, cut, cwm, defile, dell,
   dike, ditch, donga, draw, dry bed, excavation, fault, fissure,
   flaw, flume, fracture, furrow, gap, gape, gash, gorge, groove,
   gulf, gully, gullyhole, headrace, hole, incision, irrigation ditch,
   joint, kloof, leak, moat, notch, nullah, opening, pass, passage,
   race, ravine, rent, rift, rime, river bed, riverway, runnel,
   rupture, scissure, seam, slit, slot, sluice, spillbox, spillway,
   split, stream bed, streamway, swash, swash channel, tailrace,
   trench, valley, void, wadi, water carrier, water channel,
   water furrow, water gap, water gate, watercourse, waterway,
   waterworks