Source : Webster's Revised Unabridged Dictionary (1913)

Larkspur \Lark"spur\, n. (Bot.)
   A genus of ranunculaceous plants ({Delphinium}), having showy
   flowers, and a spurred calyx. They are natives of the North
   Temperate zone. The commonest larkspur of the gardens is {D.
   Consolida}. The flower of the bee larkspur ({D. elatum}) has
   two petals bearded with yellow hairs, and looks not unlike a
   bee.

Source : WordNet®

larkspur
     n : any of numerous cultivated plants of the genus Delphinium