- a disease caused by a deficiency of niacin in the diet, characterized by skin changes, severe nerve dysfunction, mental symptoms, and diarrhea.
- pathol a disease caused by a dietary deficiency of nicotinic acid, characterized by burning or itching often followed by scaling of the skin, inflammation of the mouth, diarrhoea, mental impairment, etc
n.chronic disease caused by dietary deficiency and characterized by skin eruptions, 1811, a hybrid formed from Latin pellis “skin” (see film (n.)) + Greek agra “a catching, seizure,” related to agrein “to take, seize.” But OED suggests it might be originally Italian pelle agra “rough skin.” Related: Pellagrous. n.
- A disease caused by a deficiency of niacin and protein in the diet and characterized by skin eruptions, digestive and nervous system disturbances, and eventual mental deterioration.
- A disease caused by a lack of niacin in the diet, characterized by skin and digestive disorders and mental deterioration.