precipice

from WordNet (r) 3.0 (2006)

precipice
    n 1: a very steep cliff

from The Collaborative International Dictionary of English v.0.48

Precipice \Prec"i*pice\, n. [F. pr['e]cipice, L. praecipitium,
   fr. praeceps, -cipitis, headlong; prae before + caput,
   capitis, the head. See {Pre-}, and {Chief}.]
   1. A sudden or headlong fall. [Obs.] --Fuller.
      [1913 Webster]

   2. A headlong steep; a very steep, perpendicular, or
      overhanging place; an abrupt declivity; a cliff.
      [1913 Webster]

            Where wealth like fruit on precipices grew.
                                                  --Dryden.
      [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

25 Moby Thesaurus words for "precipice":
      bluff, cliff, crag, crest, escarpment, face, hilltop, knoll,
      lofty peak, mountaintop, palisade, palisades, peak, pic, pico,
      pike, pinnacle, point, scar, scarp, spur, steep, summit, tor,
      wall