vitamin A

a fat-soluble vitamin. Its aldehyde,retinal, is a component of the photopigments in the retina. Vitamin A deficiency results in night blindness and other visual disorders. Also called retinol. See also visual cycle.

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Psychology term of the day

January 15th 2025

overcontrolled

adj. denoting behavior that is inhibited and constrained, often driven by shyness or fear of rejection. The word is typically used to describe the behavior of children thought to be at risk for depression, but it may also refer to similar behavior in adults.