\ ˈil How to pronounce ill (audio) \
worse\ ˈwərs How to pronounce ill (audio) \; worst\ ˈwərst How to pronounce ill (audio) \

Definition of ill

 (Entry 1 of 5)

1a comparative also iller; superlative also illest
(1) : not in good health also : nauseated
(2) : not normal or sound ill health
b : causing suffering or distress ill weather
2 : unfriendly, hostile ill feeling
3a : not suited to circumstances or not to one's advantage : unlucky an ill omen
b : involving difficulty : hard
4a : attributing evil or an objectionable quality held an ill opinion of his neighbors
b : resulting from, accompanied by, or indicative of an evil or malevolent intention ill deeds
c chiefly Scotland : immoral, vicious
5a : not meeting an accepted standard ill manners
b archaic : notably unskillful or inefficient


worse; worst

Definition of ill (Entry 2 of 5)

1a : in a faulty, inefficient, insufficient, or unpleasant manner often used in combination the methods used may be ill-adapted to the aims in view— R. M. Hutchins
b : in an unfortunate manner : badly, unluckily ill fares the land … where wealth accumulates, and men decay— Oliver Goldsmith
2 : hardly, scarcely can ill afford such extravagances
3a : so as to reflect unfavorably spoke ill of the neighbors
b : with displeasure or hostility
c : in a harsh manner
4 : in a reprehensible manner



Definition of ill (Entry 3 of 5)

b(1) : ailment, sickness
(2) : something that disturbs or afflicts : trouble economic and social ills
2 : something that reflects unfavorably spoke no ill of him
3 : the reverse of good : evil

Definition of ill (Entry 4 of 5)

illustrated; illustration; illustrator

Definition of Ill (Entry 5 of 5)


Examples of ill in a Sentence

Adjective That dog can eat almost anything with no ill effects. They had been subjected to months of ill treatment. Adverb He is being ill served by his advisers. Please don't think ill of me. He was a good man who never spoke ill of anyone. Noun chicken pox and the other ills that were once a fixture of childhood idealistic people who try to cure all of our society's ills See More
Recent Examples on the Web: Adjective Yet, now and then, an American would inexplicably fall ill—no recent travel, no clear links. Beth Mole, Ars Technica, 28 July 2022 Both individuals were seriously ill with their infections, but both recovered. Helen Branswell, STAT, 28 July 2022 Despite the bad luck of falling ill while on tour, the stars have aligned for Peach PRC in the past year. Lars Brandle, Billboard, 28 July 2022 Jigme Gurung, a citizen scientist working with the WWF in upper Dolpa, has recently found numerous wild blue sheep that were severely ill or dead with mange-like symptoms and has seen camera-trap photos of other snow leopards with similar symptoms. Ben Ayers, Outside Online, 27 July 2022 Love + One International is a 501(c)3 nonprofit organization run by a mother-daughter duo that provides critically ill children in remote Uganda access to life-saving medical care and rehabilitative services at their Love + One Center. Elizabeth Berry, Woman's Day, 26 July 2022 So a weakening of that engine bodes ill for American growth and prosperity. New York Times, 26 July 2022 Ellen was with me through the tragic loss of my son and, six weeks later, my very ill husband. Abigail Van Buren, oregonlive, 22 July 2022 Those patients are usually unvaccinated, or else chronically ill or old. Globe Staff,, 22 July 2022 Recent Examples on the Web: Adverb In the early 90s, Cabakoff fell ill and resigned from the Wexner Foundation Board, Ellison said, so Epstein took her place on it. Charles Trepany, USA TODAY, 15 July 2022 Not long after, her father fell ill, was hospitalized and after his recovery, was left soured by the health care system and what the family saw as Mr. Biden’s failure to fix it. New York Times, 14 July 2022 Petschl and another student who wished not to be named emailed The Times detailing their mounting worries as the heat rose and students in stifling polyester caps and gowns fell ill. Gregory Yeestaff Writer, Los Angeles Times, 17 June 2022 In late September 2020, captive mink on a farm in Michigan suddenly fell ill. Emily Anthes,, 26 May 2022 Between September and February, four infants fell severely ill with a dangerous bacteria after consuming formula made at the plant. The Editorial Board, WSJ, 25 May 2022 Illness: Jury selection ended early on Monday after another lawyer fell ill. Victoria Ballard, Sun Sentinel, 23 May 2022 Abbott recalled formula and closed its manufacturing plant in Sturgis, Michigan, in February over concerns about bacterial contamination after four infants fell ill. Sasha Pezenik, ABC News, 21 May 2022 Two children fell seriously ill and recovered, the CDC said. Meryl Kornfield, Hannah Knowles, Anchorage Daily News, 20 May 2022 Recent Examples on the Web: Noun Despite ExxonMobil’s implications to the contrary, individual consumers cannot reverse climate change—or any other environmental ill, for that matter—and their choices are no substitute for systemic reforms. Michelle Nijhuis, The Atlantic, 22 June 2022 The director is little helped by Barrymore, whose E.T.-era button-cuteness ill-serves this particular project. Clark Collis,, 14 May 2022 Doncic committed nearly half of those, but Westbrook is receiving far more criticism for the same ill. Duane Rankin, USA TODAY, 21 Jan. 2022 Though the Republican governor opposed marijuana legalization as a social ill, her administration’s arguments in court centered on technical violations to the South Dakota Constitution. From Usa Today Network And Wire Reports, USA TODAY, 25 Nov. 2021 This societal ill seemed to peak with Princess Diana’s death in 1997 but has only gotten worse in the decades since. Michelle Ruiz, Vogue, 26 Oct. 2021 In Chinese eyes, each of its targets is associated with a longstanding social ill. WSJ, 26 Sep. 2021 The state doesn’t have enough intensive care unit beds to treat the ill. al, 9 Sep. 2021 Harris and Biden, too, have been fully vaccinated, which public health experts say should protect nearly everyone from falling serious ill. Todd J. Gillman, Dallas News, 20 July 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ill.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of ill


12th century, in the meaning defined at sense 4c


13th century, in the meaning defined at sense 3b


13th century, in the meaning defined at sense 3

History and Etymology for ill


Middle English, from Old Norse illr

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The first known use of ill was in the 12th century

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Dictionary Entries Near ill

ilka day



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Statistics for ill

Last Updated

5 Aug 2022

Cite this Entry

“Ill.” Dictionary, Merriam-Webster, Accessed 8 Aug. 2022.

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More Definitions for ill


\ ˈil How to pronounce ill (audio) \
worse\ ˈwərs \; worst\ ˈwərst \

Kids Definition of ill

 (Entry 1 of 4)

1 : not in good health : sick an ill person
2 : not normal or sound ill health
3 : meant to do harm : evil ill deeds
4 : causing suffering or distress ill weather
5 : not helpful He was plagued by ill luck.
6 : not kind or friendly ill intentions
7 : not right or proper ill manners


worse; worst

Kids Definition of ill (Entry 2 of 4)

1 : with displeasure or anger The remark was ill received.
2 : in a harsh or unkind way The animals were ill treated.
3 : scarcely sense 1, hardly He can ill afford it.
4 : in a bad or faulty way They're ill-prepared to face the winter.



Kids Definition of ill (Entry 3 of 4)

1 : the opposite of good Things will change for good or ill.
2 : a sickness or disease childhood ills
3 : trouble entry 1 sense 2 society's ills



Kids Definition of Ill.



\ ˈil How to pronounce ill (audio) \
worse\ ˈwərs How to pronounce ill (audio) \ also iller\ ˈil-​ər How to pronounce ill (audio) \; worst\ ˈwərst How to pronounce ill (audio) \

Medical Definition of ill

 (Entry 1 of 2)

1 : affected with some ailment : not in good health incurably ill with cancerTime mentally ill
2 : affected with nausea often to the point of vomiting thought she would be ill after the ride on the roller coaster



Medical Definition of ill (Entry 2 of 2)

: ailment, sickness chicken pox and other ills of childhood

Ill geographical name

\ ˈēl How to pronounce Ill (audio) \

Definition of Ill

river 129 miles (208 kilometers) long in northeastern France flowing into the Rhine River

More from Merriam-Webster on ill

Nglish: Translation of ill for Spanish Speakers

Britannica English: Translation of ill for Arabic Speakers


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