WordNet (r) 3.0 (2006):

Leucanthemum superbum
    n 1: hybrid garden flower derived from Chrysanthemum maximum and
         Chrysanthemum lacustre having large white flower heads
         resembling oxeye daisies; often placed in the genus
         Chrysanthemum [syn: shasta daisy, Leucanthemum
         superbum, Chrysanthemum maximum maximum]