lactase deficiency(n = noun.state) lactose intolerance, milk intolerance - congenital disorder consisting of an inability to digest milk and milk products; absence or deficiency of lactase results in an inability to hydrolyze lactose;
is a kind of congenital disease, genetic abnormality, genetic defect, genetic disease, genetic disorder, hereditary condition, hereditary disease, inherited disease, inherited disorder

acquired immune deficiency syndrome, color vision deficiency, colour vision deficiency, deficiency, deficiency disease, iron deficiency anaemia, iron deficiency anemia, lactase, mass deficiency, mental deficiency, mineral deficiency, vitamin deficiency, zinc deficiency