any of a genus (Delphinium) of plants of the buttercup family, bearing spikes of spurred, irregular flowers, usually blue, on tall stalks: several species are poisonous
See delphinium in American Heritage Dictionary 4
(dĕl-fĭnˈē-əm)
noun
A plant of the genus Delphinium, especially any of several tall cultivated varieties having palmate leaves and long racemes of showy, variously colored spurred flowers. Also called larkspur.