noun

illness

sickness, disease, ailment

She missed work due to a sudden illness.

She missed work due to a sudden illness.

Mental illness is a serious health issue.

Mental illness is a serious health issue.

a/an ((...)) illness a particular disease or sickness She missed work due to a sudden illness.

to suffer from ((an)) illness to be affected by a disease He suffers from a chronic illness.

Synonyms: sickness, disease, ailment; Antonyms: health, wellness

From the adjective 'ill' + the noun-forming suffix '-ness'.

Remember it as the state (-ness) of being ill. Just like 'happy' becomes 'happiness'.

This page is designed for learning support. Please use it as a learning reference, not as a formal reference.