rift

rift (http://definr.com/rift)

     n 1: a gap between cloud masses; "the sun shone through a rift in
          the clouds"
     2: a narrow fissure in rock
     3: a personal or social separation (as between opposing
        factions); "they hoped to avoid a break in relations"
        [syn: rupture, breach, break, severance, {falling
        out}]