Is it ensure, insure, or assure?
any minute, delicate insect (order Diptera) characterized by beaded, somewhat hairy antennae and few veins in the short-haired wings. The brightly coloured larvae live in leaves and flowers, usually causing the formation of tissue swellings (galls). A few live in galls produced by other dipterans. Pupation takes place in the gall or in the soil; the winter is passed in an immature stage