The Collaborative International Dictionary of English v.0.48:

nosegay \nose"gay`\, n. [Nose + gay in the sense of a gay or
   showy thing.]
   A bunch of odorous and showy flowers; a bouquet; a posy.
   --Pope.
   [1913 Webster]

WordNet (r) 3.0 (2006):

nosegay
    n 1: an arrangement of flowers that is usually given as a
         present [syn: bouquet, corsage, posy, nosegay]