The Collaborative International Dictionary of English v.0.48:

Buceros \Bu"ce*ros\, n. [Gr. boy`kerws horned like an ox; boy^s
   ox + ke`ras horn.] (Zool.)
   A genus of large perching birds; the hornbills.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Buceros
    n 1: type genus of the family Bucerotidae [syn: Buceros,
         genus Buceros]