periwinkle /ˈpɛɹ.ɪˌwɪŋ.kəl/noun 5adjective 1forms 3 noun5 •Any of several evergreen plants of the genus Vinca with blue or white flowers.The Periwinkle is a great binder, staying bleeding both at mouth and nose if some of the leaves be chewed. — 1652 •Similar plants of genus Catharanthus. •A mollusk of family Littorinidae.He was working a pin into a periwinkle shell, turning it to extract the toothsome morsel of meat. — 2022 •A color with bluish and purplish hues, somewhat light. •A caddisfly larva. adjective1 •Of pale bluish purple colour. formsperiwinkles · more periwinkle · most periwinkle