Vitamin A deficiency: Related Medical Conditions. To research the causes of Vitamin A deficiency, consider researching the causes of these these diseases that may be similar, or associated with Vitamin A deficiency:
Definition of push button. : a small button or knob that when pushed operates something especially by closing an electric circuit.
buttonhole (plural buttonholes) 1  A hole through which a button is pushed to secure a garment or some part of one. ( 2 chiefly Britain) a flower worn in a buttonhole for decoration.