the poor condition of a person’s body or mindHe retired early on grounds of ill health.Synonymsillnesssicknessill healthtroubleThese are all words for the state of being physically or mentally ill.illness the state of being physically or mentally ill.sickness illness; bad health:I recommend you get insurance against sickness and unemployment.illness or sickness?Sickness is used especially in contexts concerning work and insurance. It is commonly found with words such as pay, leave, absence and insurance. Illness has a wider range of uses and is found in more general contexts.ill health (rather formal) the state of being physically ill or having lots of health problems:She resigned because of ill health.Ill health often lasts a long period of time.trouble illness or pain:heart trouble.When trouble is used with this meaning, it is necessary to say which part of the body is affected.Patternschronic illness/sickness/ill health to suffer from illness/sickness/ill health/heart, etc. trouble
See ill health in the Oxford Learner's Dictionary of Academic EnglishSee ill health in the Oxford Advanced American Dictionary