Source : Webster's Revised Unabridged Dictionary (1913)

Gamopetalous \Gam`o*pet"al*ous\, a. [Gr. ? marriage + E.
   petalous: cf. F. gamop['e]tale.] (Bot.)
   Having the petals united or joined so as to form a tube or
   cup; monopetalous.

Source : WordNet®

gamopetalous
     adj : having a corolla composed of partially or wholly fused
           petals forming a corolla shaped like a tube or funnel
           [syn: {sympetalous}]