illness          
noun uk/ˈɪl.nəs/ us/ˈɪl.nəs/
B1 [ C ](身体或精神上的)疾病 
a disease of the body or mind
  He died at home after a long illness. 久病之后他在家里死去。 
 B2 [ U ]生病 
the state of being ill
  She had five days off work due to illness. 她因病请了5天假。 
 - More examples
 - We are lacking three members of staff due to illness.
 - Many people suffer from some form of mental illness during their lives.
 - Symptoms of the illness include a high temperature and a persistent dry cough.
 - Many illnesses which once killed are today curable.
 - Four million hours were lost last year through stress-related illnesses.