- cornflower, bachelor's button, bluebottle, Centaurea cyanus - an annual Eurasian plant cultivated in North America having showy heads of blue or purple or pink or white flowers
--1 is a kind of flower
--1 is a member of Centaurea, genus Centaurea - bluebottle, Calliphora vicina - blowfly with iridescent blue body; makes a loud buzzing noise in flight
--2 is a kind of blowfly, blow fly