A deep narrow steep-sided valley (especially one formed by running water).

Roget 198: interval, interspace^†; separation etc. 44; break, gap, opening; hole etc. 260; chasm, hiatus, caesura; interruption, interregnum; interstice, lacuna, cleft, mesh, crevice, chink, rime, creek, cranny, crack, chap, slit, fissure, scissure^†, rift, flaw, breach, rent, gash, cut, leak, dike, ha-ha.    gorge, defile, ravine, canon, crevasse, abyss, abysm; gulf; inlet, frith^†, strait, gully; pass; furrow etc. 259; abra^†; barranca^†, barranco^†; clove [U.S.], gulch [U.S.], notch [U.S.]; yawning gulf; hiatus maxime [Lat.], hiatus valde deflendus [Lat.]; parenthesis etc. (interjacence) 228^†; void etc. (absence) 187; incompleteness etc. 53.    [interval of time] period etc. 108; interim (time) 106.    ... show more

Roget 203: narrowness etc. adj.; closeness, exility^†; exiguity etc. (little) 193.    line; hair's breadth, finger's breadth; strip, streak, vein.    monolayer; epitaxial deposition [Eng.].    thinness etc. adj.; tenuity; emaciation, macilency^†, marcor^†.    shaving, slip etc. (filament) 205; thread paper, skeleton, shadow, anatomy, spindleshanks^†, lantern jaws, mere skin and bone.    middle constriction, stricture, neck, waist, isthmus, wasp, hourglass; ridge, ghaut^†, ghat^†, pass; ravine etc. 198.    narrowing, coarctation^†, angustation^†, tapering; contraction etc. 195.    ... show more

Roget 259: furrow, groove, rut, sulcus [Anat.], scratch, streak, striae, crack, score, incision, slit; chamfer, fluting; corduroy road, cradle hole.    channel, gutter, trench, ditch, dike, dyke; moat, fosse^†, trough, kennel; ravine etc. (interval) 198; tajo [U.S.], thank-ye-ma'am [U.S.].    ... show more

Dutch: ravijn
Polish: wąwóz