'Illness' definitions:

Definition of 'illness'

From: WordNet
noun
Impairment of normal physiological function affecting part or all of an organism [syn: illness, unwellness, malady, sickness] [ant: health, wellness]

Definition of 'Illness'

From: GCIDE
  • Illness \Ill"ness\, n. [From Ill.]
  • 1. The condition of being ill, evil, or bad; badness; unfavorableness. [Obs.] "The illness of the weather." --Locke. [1913 Webster]
  • 2. Disease; indisposition; malady; disorder of health; sickness; as, a short or a severe illness. [1913 Webster]
  • 3. Wrong moral conduct; wickedness. --Shak.
  • Syn: Malady; disease; indisposition; ailment.
  • Usage: Illness, Sickness. Within the present century, there has been a tendency in England to use illness in the sense of a continuous disease, disorder of health, or sickness, and to confine sickness more especially to a sense of nausea, or "sickness of the stomach." [1913 Webster]

Synonyms of 'illness'

From: Moby Thesaurus