disease
n. C / Un. an illness or medical condition that stops your body or mind from working normally. It is often caused by germs, your genes, or your lifestyle.
n. a pathological condition of a body part, organ, or system resulting from various causes, such as infection, genetic defect, or environmental stress. Characterised by an identifiable group of signs or symptoms.
The doctor is studying a rare heart disease.
Vaccinations have helped to eliminate many infectious diseases that used to be very dangerous for children.
While some chronic diseases are the result of genetic predispositions, many others are exacerbated by environmental factors and sedentary lifestyle choices common in modern urban settings.
From Middle English disese, from Anglo-Norman desese, disaise, from Old French desaise, from des- + aise. Displaced native Middle English adle, audle (“disease”) (from Old English ādl (“disease, sickness”), see adle), Middle English cothe, coathe (“disease”) (from Old English coþu (“disease”), see coath). By surface analysis, dis- + ease.
Uncountable when referring to the general state of being ill; countable when referring to specific medical conditions.
He has a strong diseaseHe has a serious diseaseLearners often use 'strong' to describe intensity, but 'serious' or 'severe' are the standard collocations for medical conditions.