a disease caused by deficiency of niacin or tryptophan (or by a defect in the metabolic conversion of tryptophan to niacin); characterized by gastrointestinal disturbances and erythema and nervous or mental disorders; may be caused by malnutrition or alcoholism or other nutritional impairments
a single written symbol that represents an entire word or phrase without indicating its pronunciation; "7 is a logogram that is pronounced `seven' in English and `nanatsu' in Japanese"