[syn: depth, deepness]
4.  a low pitch that is loud and voluminous; 
The Collaborative International Dictionary of English v.0.48:
Deepness \Deep"ness\, n.
   1. The state or quality of being deep, profound, mysterious,
      secretive, etc.; depth; profundity; -- opposed to
      shallowness.
      [1913 Webster]
            Because they had no deepness of earth. --Matt. xiii.
                                                  5.
      [1913 Webster]
   2. Craft; insidiousness. [R.] --J. Gregory.
      [1913 Webster]
WordNet (r) 3.0 (2006):
deepness
    n 1: the intellectual ability to penetrate deeply into ideas
         [syn: astuteness, profundity, profoundness, depth,
         deepness]
    2: the quality of being physically deep; "the profundity of the
       mine was almost a mile" [syn: deepness, profundity,
       profoundness] [ant: shallowness]
    3: the extent downward or backward or inward; "the depth of the
       water"; "depth of a shelf"; "depth of a closet" [syn:
       depth, deepness]
    4: a low pitch that is loud and voluminous