Any loss/abnomality of physiological/psychological/ anatomical structure or function is
According to WHO definitions,
Disease: Any abnormal condition of an individual that impairs function.
Impairment: Any loss or abnormality of psychological, physiological or anatomical structure or function.
Disability: (Because of impairment,) any restriction or inability to perform an activity in a range considered normal for a human being
Handicap: A disadvantage for a given individual, resulting from an impairment/disability, that limits/prevents fulfillment of a role considered normal (depending on age, sex, social, cultural factors) for that individual
Disease
Impairment
Disability
Handicap