The Collaborative International Dictionary of English v.0.48:

Breccia \Brec"cia\, n. [It., breach, pebble, fragments of stone,
   fr. F. br[`e]che; of German origin. See Breach.] (Geol.)
   A rock composed of angular fragments either of the same
   mineral or of different minerals, etc., united by a cement,
   and commonly presenting a variety of colors.
   [1913 Webster]

   Bone breccia, a breccia containing bones, usually
      fragmentary.

   Coin breccia, a breccia containing coins.
      [1913 Webster]

WordNet (r) 3.0 (2006):

breccia
    n 1: a rudaceous rock consisting of sharp fragments embedded in
         clay or sand

Moby Thesaurus II by Grady Ward, 1.0:

58 Moby Thesaurus words for "breccia":
   aa, abyssal rock, agglomerate, agglomeration, basalt, bedrock,
   block lava, brash, bunch, clot, cluster, concrete, concretion,
   conglomerate, conglomeration, crag, debris, detritus, druid stone,
   festooned pahoehoe, gneiss, grain, granite, granule, granulet,
   gravel, grit, igneous rock, lava, limestone, living rock, magma,
   mantlerock, mass, metamorphic rock, monolith, pahoehoe,
   pillow lava, porphyry, pudding stone, regolith, rock, ropy lava,
   rubble, rubblestone, sand, sandstone, sarsen, schist, scoria,
   scree, sedimentary rock, shelly pahoehoe, shingle, stone, talus,
   tufa, tuff