The Collaborative International Dictionary of English v.0.48:

Dodo \Do"do\, n.; pl. Dodoes. [Said to be fr. Pg. doudo silly,
   foolish (cf. Booby); this is fr. Prov. E. dold, the same
   word as E. dolt.] (Zool.)
   A large, extinct bird (Didus ineptus), formerly inhabiting
   the Island of Mauritius. It had short, half-fledged wings,
   like those of the ostrich, and a short neck and legs; --
   called also dronte. It was related to the pigeons.
   [1913 Webster]

WordNet (r) 3.0 (2006):

dodo
    n 1: someone whose style is out of fashion [syn: dodo, fogy,
         fogey, fossil]
    2: extinct heavy flightless bird of Mauritius related to pigeons
       [syn: dodo, Raphus cucullatus]