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Synonyms

ill

1 American  
[il] / ɪl /

adjective

worse, worst, iller, illest
  1. of unsound physical or mental health; unwell; sick.

    She felt ill, so her teacher sent her to the nurse.

    Synonyms:
    afflicted, diseased, ailing, unhealthy
    Antonyms:
    healthy, well
  2. objectionable; unsatisfactory; poor; faulty.

    ill manners.

  3. hostile; unkindly.

    ill feeling.

  4. evil; wicked; bad.

    of ill repute.

    Synonyms:
    iniquitous, wrong
    Antonyms:
    good
  5. unfavorable; adverse.

    ill fortune.

  6. of inferior worth or ability; unskillful; inexpert.

    an ill example of scholarship.

  7. Slang. great; amazing.

    His mom is the illest cook.


noun

  1. an unfavorable opinion or statement.

    I can speak no ill of her.

  2. harm or injury.

    His remarks did much ill.

    Synonyms:
    misery, affliction, pain, hurt
  3. trouble, distress, or misfortune.

    Many ills befell him.

    Synonyms:
    calamity
  4. evil.

    to know the difference between good and ill.

    Synonyms:
    depravity
  5. sickness or disease.

    Synonyms:
    affliction, illness

adverb

  1. in an ill manner.

  2. unsatisfactorily; poorly.

    It ill befits a man to betray old friends.

  3. in a hostile or unfriendly manner.

  4. unfavorably; unfortunately.

  5. with displeasure or offense.

  6. faultily; improperly.

  7. with difficulty or inconvenience; scarcely.

    Buying a new car is an expense we can ill afford.

idioms

  1. ill at ease, socially uncomfortable; nervous.

    They were ill at ease because they didn't speak the language.

I'll 2 American  
[ahyl] / aɪl /
  1. contraction of I will.


ill. 3 American  

abbreviation

  1. illustrated.

  2. illustration.

  3. illustrator.

  4. most illustrious.


Ill. 4 American  

abbreviation

  1. Illinois.


ill 1 British  
/ ɪl /

adjective

  1. (usually postpositive) not in good health; sick

  2. characterized by or intending evil, harm, etc; hostile

    ill deeds

  3. causing or resulting in pain, harm, adversity, etc

    ill effects

  4. ascribing or imputing evil to something referred to

    ill repute

  5. promising an unfavourable outcome; unpropitious

    an ill omen

  6. harsh; lacking kindness

    ill will

  7. not up to an acceptable standard; faulty

    ill manners

  8. unable to relax; uncomfortable

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

  1. evil or harm

    to wish a person ill

  2. a mild disease

  3. misfortune; trouble

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

adverb

  1. badly

    the title ill befits him

  2. with difficulty; hardly

    he can ill afford the money

  3. not rightly

    she ill deserves such good fortune

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Ill. 2 British  

abbreviation

  1. Illinois

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

I'll 3 British  
/ aɪl /

contraction

  1. I will or I shall

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

ill More Idioms  

    More idioms and phrases containing ill


Grammar

See well 1.

Usage

What are other ways to say ill? The adjective ill is defined as “evil; wicked; bad.” However, it’s not used in exactly the same way as any of those synonyms! Learn the difference among these terms on Thesaurus.com.

Related Words

Ill, sick mean being in bad health, not being well. Ill is the more formal word. In the U.S. the two words are used practically interchangeably except that sick is always used when the word modifies the following noun: He looks sick ( ill ); a sick person. In England, sick is not interchangeable with ill, but usually has the connotation of nauseous: She got sick and threw up. sick, however, is used before nouns just as in the U.S.: a sick man.

Etymology

Origin of ill1

1150–1200; Middle English ill ( e ) (noun and adj.) < Old Norse illr (adj.) ill, bad

Origin of ill.3

ill. ( def. 4 ) < Latin illustrissimus

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“The Housemaid” would be enjoyable enough had Seyfried only been giving a layered performance as a mentally ill housewife.

From Salon

The fumes from the cauldron were making him thickheaded and ill, but he shook himself.

From Literature

"People go into hospital and some people die. People get ill and die," Dervin says.

From BBC

Sarah Daniels was constantly in her overdraft after losing her job due to ill health in 2024, eventually ending up £5,000 in the red.

From BBC

The 38-year-old read about Chinese ill treatment of the ethnic Uyghurs from foreign sources on the internet, and he traveled to Xinjiang province at great personal risk to see for himself.

From The Wall Street Journal