NCIt definition : A disorder that is caused by the deficiency of a vitamin. The deficiency may result
from either suboptimal vitamin intake or conditions that prevent the vitamin's use
or absorption in the body. Representative examples include beriberi caused by thiamine
deficiency, scurvy caused by vitamin C deficiency, and rickets caused by vitamin D
deficiency.;
Alternative definition : FDA: Low levels of one or more vitamins in the body.;