[1] : The Collaborative International Dictionary of English v.0.48

pachyderm \pach"yderm\ pa^k"i^d~erm, n. cf. f.
   pachyderme. zool.
   any of various nonruminant hoofed mammals having very thick
   skin, including the elephant, rhinoceros, and
   hippopotamus, one of the pachydermata.
   wordnet 1.5 + 1913 webster
see also:
elephant rhinoceros hippopotamus 

[2] : The Collaborative International Dictionary of English v.0.48

rhinoceros \rhinoc"eros\ r-ino^s"-ero^s, n. l.,
   fr. gr. "rinoke`rws, "rinoke`rwtos; "ri`s, "rino`s, the nose
   + ke`ras a horn: cf. f. rhinoc'eros. see horn. zool.
   any pachyderm belonging to the genera rhinoceros,
   atelodus, and several allied genera of the family
   rhinocerotidae, of which several living, and many extinct,
   species are known. they are large and powerful, and usually
   have either one or two stout conical median horns on the
   snout.
   1913 webster

   note: the indian, or white, and the javan rhinoceroses
         rhinoceros indicus and rhinoceros sondaicus have
         incisor and canine teeth, but only one horn, and the
         very thick skin forms shieldlike folds. the two or
         three african species belong to atelodus, and have
         two horns, but lack the dermal folds, and the incisor
         and canine teeth. the two malay, or east indian,
         two-horned species belong to ceratohinus, in which
         incisor and canine teeth are present. see borele, and
         keitloa.
         1913 webster

   rhinoceros auk zool., an auk of the north pacific
      cerorhina monocrata which has a deciduous horn on top
      of the bill.

   rhinoceros beetle zool., a very large beetle of the genus
      dynastes, having a horn on the head.

   rhinoceros bird. zool.
   a a large hornbill buceros rhinoceros, native of the
       east indies. it has a large hollow hornlike process on
       the bill. called also rhinoceros hornbill. see
       hornbill.
   b an african beefeater buphaga africana. it alights on
       the back of the rhinoceros in search of parasitic
       insects.
       1913 webster
see also:
horn rhinoceros atelodus rhinocerotidae rhinoceros indicus rhinoceros sondaicus 
ceratohinus borele keitloa rhinoceros auk cerorhina monocrata 
rhinoceros beetle dynastes rhinoceros bird buceros rhinoceros rhinoceros hornbill 
hornbill buphaga africana 

[3] : WordNet (r) 2.0

rhinoceros
     n : massive powerful herbivorous odd-toed ungulate of southeast
         asia and africa having very thick skin and one or two
         horns on the snout syn: rhino
see also:
rhino 

Rhinoceros >> R Words
Rhinoceros, definition of term: Rhinoceros
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