abnormalityEnglishOxford New American Dictionaryabnormality /ˌabnôrˈmalədē, ˌæbnɔrˈmælədi / ▸ noun (plural abnormalities) an abnormal feature, characteristic, or occurrence, typically in a medical context: a chromosome abnormality. ▪ the quality or state of being abnormal: miscarriage can be caused by fetal abnormality.