umbo

2 definitions found

umbo - Collaborative International Dictionary of English v.0.48 :

  Umbo \Um"bo\, n.; pl. L. Umbones, E. Umbos. [L.]
     1. The boss of a shield, at or near the middle, and usually
        projecting, sometimes in a sharp spike.
        [1913 Webster]
  
     2. A boss, or rounded elevation, or a corresponding
        depression, in a palate, disk, or membrane; as, the umbo
        in the integument of the larvae of echinoderms or in the
        tympanic membrane of the ear.
        [1913 Webster]
  
     3. (Zool.) One of the lateral prominences just above the
        hinge of a bivalve shell.
        [1913 Webster] Umbonate

umbo - WordNet (r) 2.1 (2005) :

  umbo
      n 1: a slight rounded elevation where the malleus attaches to
           the eardrum