rift

1 an irregular usually narrow break in a surface created by pressure <a small rift opened in the earth's crust> Synonyms check, chink, cleft, cranny, crevice, fissure, crack, splitRelated Words crevasse; craze, hairline; fracture, rupture; breach, gap, opening; cut, gash, incision, slit

2 an open space in a barrier (as a wall or hedge) <it was possible to peek through the rift in the fence and see the ball game> Synonyms breach, break, discontinuity, gulf, hiatus, hole, interstice, interval, opening, rent, gap, separation, voidRelated Words chink, cleft, crack, cranny, crevice, fissure; notch, slit, slot, split; interspace, pore; abyss, aperture, cavity, chasm, gape, orifice; fracture, rupture, severance, sundering