adjective

ill

ihl

adjective

Unwell or in poor health; sick.

"She stayed home from work because she felt ill."

"He was seriously ill for most of last winter."

Bad, harmful, or unfavourable.

"The decision had some unexpected ill effects on morale."

adverb

Badly or imperfectly.

"The plan was ill conceived from the very start."

noun

A problem, hardship, or misfortune (usually plural).

"The report examined the social ills of poverty and unemployment."

How to Use Ill

Learner’s notes

In plain EnglishMost commonly means "sick," but as an adverb/prefix it also means "badly" (ill-advised, ill-timed).

UK vs US

British English uses "ill" for "sick" more often in everyday speech than American English, which tends to prefer "sick."

Common pairings

fall ill critically ill ill health ill-advised social ills

Word Forms

iller comparative, more ill comparative, worse comparative, more ill comparative, illed past tense, ills plural, ills singular, illest superlative, most ill superlative, worst superlative, most ill superlative

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Can you complete this real example?

She stayed home from work because she felt _____.

Etymology

From Old Norse illr, "bad, evil," related to Danish ilde and Swedish illa.

Synonyms

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bad mal- crank crook green about the gills icky indisposed infirm like death warmed over lousy maladive mawkish

Antonyms

fine hale healthy in good health well good wack

Related Words

good bad OK bend beautiful spoilt penis dead

Rhymes for ill

kill mill sill bill will till hill fill Jill dill gill pill

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bad mal- crank crook green about the gills icky indisposed infirm like death warmed over lousy maladive mawkish