ILLNESS

illness, unwellness, malady, sickness

(noun) impairment of normal physiological function affecting part or all of an organism

Source: WordNet® 3.1

Etymology

Noun

illness (countable and uncountable, plural illnesses)

(countable) An instance of a disease or poor health.

(uncountable) A state of bad health or disease.

Synonyms

• (instance): sickness

• (state): sickness

• See also disease

Source: Wiktionary

Ill"ness, n. Etym: [From Ill.]

1. The condition of being ill, evil, or bad; badness; unfavorableness. [Obs.] "The illness of the weather." Locke.

2. Disease; indisposition; malady; disorder of health; sickness; as, a short or a severe illness.

3. Wrong moral conduct; wickedness. Shak.

Syn.

– Malady; disease; indisposition; ailment.

– 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."

Source: Webster’s Unabridged Dictionary 1913 Edition