n. & v.
n. 1 a a crack or split in an object. b an opening in a cloud etc. 2 a cleft or fissure in earth or rock. 3 a disagreement; a breach in friendly relations.
v.tr. tear or burst apart. rift-valley a steep-sided valley formed by subsidence of the earth's crust between nearly parallel faults. riftless adj. rifty adj.
[ ME, of Scand. orig. ]