Definition of ill in English:

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Pronunciation: /il/


1Not in full health; sick: her daughter is seriously ill [with submodifier]: a terminally ill patient
More example sentences
  • Leaders of our medical organisations should not allow informed consent to interfere with clinical management of infectious disease or seriously ill patients.
  • Two other patients are critically ill after contracting the disease through infected organs from the donor.
  • Siti said that volunteers should also understand that terminally ill patients usually suffer from psychological strain due to their illness.
unwell, sick, not (very) well, ailing, poorly, sickly, peaked, indisposed, infirm;
out of sorts, not oneself, bad, off, in a bad way, far gone;
bedridden, valetudinarian;
queasy, nauseous, nauseated
informal under the weather, laid up, rotten, crummy, lousy, pukey, dizzy, woozy, green around the gills, like death warmed over
2 [attributive] Poor in quality: ill judgment dogs the unsuccessful
More example sentences
  • It was because of her ill judgment.
  • Is their any provision to ban an umpire for his attitude problems and making of ill decisions?
bad, poor, incompetent, unsatisfactory, inadequate, inexpert, deficient
2.1Harmful: she had a cup of the same wine and suffered no ill effects
More example sentences
  • However, the average life of an Indian was 62 as the ill effects of cancer were visible only at a later stage in life.
  • I have always known the ill effects of smoking but did not know how harmful it could be.
  • By far the most serious ill effect of the sun is skin cancer.
harmful, damaging, detrimental, deleterious, adverse, injurious, hurtful, destructive, pernicious, dangerous;
unhealthy, unwholesome, poisonous, noxious
literary malefic, maleficent
2.2Hostile: it did give rise to a lot of ill feelings
hostile, antagonistic, acrimonious, inimical, antipathetic;
unfriendly, unsympathetic, unkind;
resentful, spiteful, malicious, vindictive, malevolent, bitter
2.3(Especially of fortune) not favorable: no one less deserved such ill fortune than McStay
More example sentences
  • As explained elsewhere, the trip to Brisbane, or more precisely the trip back, was a journey of ill omen for young Les as it threw him into the close company of Tim O'Sullivan.
  • To cap Flanagan's misfortune, he punctured with 15 miles to go and there was an immediate charge from the front of his bunch, capitalising on his ill luck.
  • During that journey, we once again encounter an ill omen in nature: in this instance, a turtle trapped on its back beneath a big rock.
unlucky, adverse, unfavorable, unfortunate, unpropitious, inauspicious, unpromising, infelicitous, ominous, sinister
literary direful


1 [usually in combination] Badly, wrongly, or imperfectly: some of his premises seem ill-chosen it ill becomes one so beautiful to be gloomy
More example sentences
  • The Bosnian government was ill prepared to defend the country with no army and only a poorly equipped territorial defense force.
  • I must be that inexplicably angry, obtuse, ill mannered, audacious, pompous blow-hard that writes insulting letters to The Peak!
  • The big worry is that the cash-strapped Irish health service is ill equipped to deal with an epidemic of any form, least of all a potentially fatal virus like SARS.
poorly, badly, imperfectly
unfavorably, adversely, badly, inauspiciously
inadequately, unsatisfactorily, insufficiently, imperfectly, poorly, badly
1.1Unfavorably or unpropitiously: something which boded ill for unwary golfers
More example sentences
  • I just watched ten minutes of speculation on whether a long deliberation bodes well or ill for the defense.
2Only with difficulty; hardly: she could ill afford the cost of new curtains
More example sentences
  • This loss of time could be ill afforded at a time when the technical preparations for Mike were at a critical stage.
  • He stressed that some of the goods produced locally lacked quality and were produced at a comparatively higher cost making such goods ill equipped to compete on the regional market.
  • Culpeper's deepest desire was to make herbal medicine available to everyone, especially the poor who could ill afford to visit a physician.
barely, scarcely, hardly, only just, (only) with difficulty, just possibly


1 (as plural noun the ill) People who are ill: a day center for the mentally ill
More example sentences
  • During the bloody war in Bosnia, various drug companies donated tons of their medicines to treat the war's wounded and the ill.
  • Apparently, the system is working pretty well, as even the ill can see that they are getting a good deal.
  • Countries all over the world are grappling with how to end the lives of the ill.
2 (usually ills) A problem or misfortune: a lengthy work on the ills of society
More example sentences
  • As tempting as it is to demonise computer games for society's ills, the evidence does not suggest such a simple link.
  • Of all the social ills and problems plaguing Bihar, sati was never on the list.
  • Both of them believe that society's ills can be fixed by putting the right man at the top to make laws and crack down on the wrong people.
problems, troubles, evils, difficulties, misfortunes, trials, tribulations;
worries, anxieties, concerns
informal headaches, hassles
archaic travails
illnesses, ailments, disorders, complaints, afflictions, sicknesses, diseases, maladies, infirmities
2.1Evil; harm: how could I wish him ill?
More example sentences
  • I want to state that I do not wish ill upon any person, and this is in fact another part of the problem.
  • I don't want to speak for anyone else, but people here generally are Democrats and wish political ill on the Republicans.
  • I wish her no ill at this stage in the competition.
harm, hurt, injury, damage, pain, trouble, misfortune, suffering, distress


On the punctuation of ill in compound adjectives, see well1 (usage), as the same rules apply.



ill at ease

Pronunciation: /ˌil əd ˈēz/
Uncomfortable or embarrassed.
Example sentences
  • Why did he seem so ill at ease, so uncomfortable with the role he had to play?
  • She had become very uncomfortable and ill at ease when visiting her parents and suffered chronic tension.
  • It made him uncomfortable and ill at ease, and he felt she was trying to keep him there in the pilothouse.
awkward, uneasy, uncomfortable, embarrassed, self-conscious, out of place, inhibited, gauche;
restless, restive, fidgety, discomfited, worried, anxious, on edge, edgy, nervous, tense, high-strung
informal twitchy, jittery, discombobulated, antsy

speak (or think) ill of

Say (or think) something critical about.
Example sentences
  • He was a handsome man, too handsome to be thought ill of by anyone, his aloof attitude did only add attractions to his charm.
  • Brown is unusual in contemporary poetry for her willingness to be thought ill of.
  • Unless one thinks ill of the woman he married, one can hardly regard this as ‘earned.’
denigrate, disparage, criticize, be critical of, speak badly of, be malicious about, blacken the name of, run down, insult, abuse, attack, revile, malign, vilify, slur
informal badmouth, dis, bitch about, talk smack, slag
formal derogate
rare asperse


Middle English (in the senses 'wicked', 'malevolent', 'harmful', and 'difficult'): from Old Norse illr 'evil, difficult', of unknown origin.

  • Ill is from Old Norse illr ‘evil’, and the commonest modern sense, ‘suffering from an illness or feeling unwell’, developed in the later medieval period. Before then a person would be sick, as they still are in the USA. The idea of harm and evil is prominent in many English proverbs, such as it's an ill wind that blows nobody any good. This refers to the days of sailing ships. The wind might be blowing in the wrong direction for you, but it was sure to be blowing the right way for someone, somewhere—it would be a very bad or ‘ill’ wind that was of no help to anyone.

Words that rhyme with ill

bill, Brazil, brill, Camille, chill, cookchill, dill, distil (US distill), downhill, drill, Edgehill, Estoril, fill, freewill, frill, fulfil (US fulfill), Gill, goodwill, grill, grille, hill, instil, kill, krill, mil, mill, nil, Phil, pill, quadrille, quill, rill, Seville, shill, shrill, sill, skill, spadille, spill, squill, still, stock-still, swill, thill, thrill, till, trill, twill, until, uphill, will

For editors and proofreaders

Syllabification: ill

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