ill

¹

[ il ]

adjective

iller illest worse worst

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.

I'll

²

[ ahyl ]

1. contraction of I will.

ill.

³

abbreviation for

1. illustrated.
2. illustration.
3. illustrator.
4. most illustrious.

Ill.

⁴

abbreviation for

1. Illinois.

Ill.

¹

abbreviation for

1. Illinois

I'll

²

/ aɪl /

contraction of

1. I will or I shall

ill

³

/ 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. ill at ease
   unable to relax; uncomfortable

noun

1. evil or harm

   to wish a person ill

2. a mild disease
3. misfortune; trouble

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

Usage Note

See contraction.

Grammar Note

See well ¹.

Word History and Origins

Origin of ill¹

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

Origin of ill²

ill. ( def 4 ) < Latin illustrissimus

Word History and Origins

Origin of ill¹

C11 (in the sense: evil): from Old Norse illr bad

Idioms and Phrases

Idioms

1. ill at ease, socially uncomfortable; nervous:

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

More idioms and phrases containing ill

• get sick

Synonym Study

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.

Example Sentences

A study in the Netherlands found that most patients who have been ill for 10 days are already making their own antibodies against the virus.

From Science News

None have been proven yet, and much of the federal and private funding for clinical trials has gone for treating the severely ill.

From Science News

In places where most people wore masks, those who did get infected seemed dramatically less likely to get severely ill compared to places with less mask-wearing.

From No Straight News

The following day he felt ill and tested positive for the coronavirus.

From No Straight News

Volunteers who were either ill, recovered or healthy all coughed at about the same velocity.

From Science News For Students

They had rarely seen their own fathers carry small children unless their mothers were ill.

From The Daily Beast

I am fortunate that I have never been deathly ill, but whenever I have the stomach flu, I most certainly feel like I am dying.

From The Daily Beast

David Prowse, the actor who portrayed Darth Vader, wished to come back but had to turn down the role because of ill health.

From The Daily Beast

But Seligman never imagined how Mitchell might put the concept to work, in part because it was so ill-suited to that purpose.

From The Daily Beast

There is a procedure called “compassionate release” allowing terminally ill men to die at home.

From The Daily Beast

These differences of interests will lead to disputes, ill blood, and finally to separation.

From Project Gutenberg

And for fear of being ill spoken of weep bitterly for a day, and then comfort thyself in thy sadness.

From Project Gutenberg

G was a gamester, who had but ill-luck; H was a Hunter, who hunted a buck.

From Project Gutenberg

"It is ill-fated;" and Alessandro blamed himself for having forgotten her only association with the name.

From Project Gutenberg

The Marshals were inclined to attribute their disgrace to the ill-will of Berthier and not to the temper of Napoleon.

From Project Gutenberg

Related Words

• abuse
• affliction
• ailment
• disease
• disorder
• evil
• illness
• infirmity
• malady
• malaise
• misery
• pain
• sickness
• suffering
• syndrome
• trouble
• woe

When To Use

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.