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¹ill

adjective \ˈil\

: not well or healthy : sick or unhealthy

of health : not normal or good

: harmful or damaging

worse \ˈwərs\ worst \ˈwərst\

Full Definition of ILL

1

a chiefly Scottish : immoral, vicious

b : resulting from, accompanied by, or indicative of an evil or malevolent intention <ill deeds>

c : attributing evil or an objectionable quality <held an ill opinion of his neighbors>

2

a : causing suffering or distress <ill weather>

b comparative also ill·er superlative also illest (1) : not normal or sound <ill health> (2) : not in good health; also : nauseated

3

a : not suited to circumstances or not to one's advantage : unlucky <an ill omen>

b : involving difficulty : hard

4

a : not meeting an accepted standard <ill manners>

b archaic : notably unskillful or inefficient

5

: unfriendly, hostile <ill feeling>

See ill defined for English-language learners

See ill defined for kids

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Origin of ILL

Middle English, from Old Norse illr

First Known Use: 12th century

Related to ILL

Synonyms: nauseous, nauseated, qualmish, queasy (also queazy), queer, queerish, sick, sickish, squeamish

Antonyms: anodyne, benign, harmless, hurtless, innocent, innocuous, inoffensive, safe

Other Medicine Terms

analgesia, angina, diabetes, hepatitis, homeopathy, logorrhea, palliate, pandemic

Rhymes with ILL

bill, brill, chill, dill, drill, fill, frill, gill, grill, grille, hill, kill, krill, mil, mill, mille, nil, nill, Phil, pill, prill, quill, rill, shill, shrill, sill, skill, spill, squill, still, swill, thill, thrill, til, till, trill, twill, vill, will

²ill

adverb

: in a bad or imperfect way

: in an unfavorable or unkind way

worseworst

Full Definition of ILL

1

a : with displeasure or hostility

b : in a harsh manner

c : so as to reflect unfavorably <spoke ill of the neighbors>

2

: in a reprehensible manner

3

: hardly, scarcely <can ill afford such extravagances>

4

a : in an unfortunate manner : badly, unluckily <ill fares the land … where wealth accumulates, and men decay — Oliver Goldsmith>

b : 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>

See ill defined for English-language learners

First Known Use of ILL

13th century

Related to ILL

Synonyms: brutally, hard, harshly, hardly, oppressively, roughly, severely, sternly, stiffly

Antonyms: clemently, gently, leniently, lightly, mildly, softly

³ill

noun

: bad or unlucky things

: a sickness or disease

ills : troubles or problems

Full Definition of ILL

1

: the reverse of good : evil

2

a : misfortune, distress

b (1) : ailment, sickness (2) : something that disturbs or afflicts : trouble <economic and social ills>

3

: something that reflects unfavorably <spoke no ill of him>

See ill defined for English-language learners

First Known Use of ILL

13th century

Related to ILL

Synonyms: affection, ail, ailment, bug, complaint, complication, condition, disorder, distemper, distemperature, fever, disease, illness, infirmity, malady, sickness, trouble

Antonyms: health, wellness

⁴ill

abbreviation

Definition of ILL

illustrated; illustration; illustrator

Ill

abbreviation

Definition of ILL

Illinois

Ill

geographical name \ˈēl\

Definition of ILL

river 129 miles (208 kilometers) NE France flowing into the Rhine

ILL Defined for Kids

¹ill

adjective \ˈil\

worse \ˈwərs\worst \ˈwərst\

Definition of ILL for Kids

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>

²ill

adverb

worseworst

Definition of ILL for Kids

1

: with displeasure or anger <The remark was ill received.>

2

: in a harsh or unkind way <The animals were ill treated.>

3

: scarcely 1, hardly <He can ill afford it.>

4

: in a bad or faulty way <They're ill-prepared to face the winter.>

³ill

noun

Definition of ILL for Kids

1

: the opposite of good <Things will change for good or ill.>

2

: a sickness or disease <childhood ills>

3

: ¹trouble 2 <society's ills>

Learn More About ILL

Thesaurus: All synonyms and antonyms for "ill"

Spanish Central: Spanish translation of "ill"

Nglish: Translation of "ill" for Spanish speakers

Britannica English: Translation of "ill" for Arabic speakers

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