Wadi :  (noun)

1: gully or streambed in northern Africa and the Middle East that remains dry except during rainy season

abysm, abyss, adolescent stream, aqueduct, arroyo, beck, bed, bottom, bottom glade, bottoms, bourn, box canyon, braided stream, branch, breach, break, brook, brooklet, burn, canal, canyon, cavity, channel, chap, chasm, check, chimney, chink, cleft, cleuch, clough, col, coulee, couloir, crack, cranny, creek, creek bed, crevasse, crevice, crick, culvert, cut, cwm, dale, defile, dell, dike, dingle, ditch, donga, draw, dry bed, excavation, fault, fissure, flaw, flowing stream, flume, fluviation, fracture, fresh, freshet, furrow, gap, gape, gash, gill, glen, gorge, groove, grove, gulch, gulf, gully, gullyhole, headrace, hole, incision, intervale, irrigation ditch, joint, kill, kloof, lazy stream, leak, lunar rill, meandering stream, midchannel, midstream, millstream, moat, moving road, navigable river, notch, nullah, opening, pass, passage, race, racing stream, ravine, rent, rift, rime, river, river bed, riverway, rivulet, run, rundle, runlet, runnel, rupture, scissure, seam, sike, slit, slot, sluice, spill stream, spillbox, spillway, split, strath, stream, stream action, stream bed, streamlet, streamway, subterranean river, swash, swash channel, tailrace, trench, trough, vale, valley, void, water carrier, water channel, water furrow, water gap, water gate, watercourse, waterway, waterworks,