The Collaborative International Dictionary of English v.0.48:

gosmore \gosmore\ n. (Bot.)
   A European weed (Hypochaeris radicata) widely naturalized
   in North America having yellow flower heads and leaves
   resembling a cat's ears.

   Syn: cat's-ear, cat's ear, California dandelion, capeweed,
        Hypochaeris radicata.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

gosmore
    n 1: European weed widely naturalized in North America having
         yellow flower heads and leaves resembling a cat's ears
         [syn: cat's-ear, California dandelion, capeweed,
         gosmore, Hypochaeris radicata]