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.
1. 1  a push button on a telephone or key on a computer keyboard that is marked with a pound sign 2  (#). a push button on a telephone or key on a computer keyboard that is marked with a pound sign (#).