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Synonyms

sickly

American  
[sik-lee] / ˈsɪk li /

adjective

sicklier, sickliest
  1. not strong; unhealthy; ailing.

    Synonyms:
    infirm, feeble, sick, puny, weak, frail
  2. of, connected with, or arising from ill health.

    a sickly complexion.

  3. marked by the prevalence of ill health, as a region.

    the epidemic left the town sickly.

  4. causing sickness.

  5. nauseating.

  6. maudlin and insipid; mawkish.

    sickly sentimentality.

  7. faint or feeble, as light or color.


adverb

  1. in a sick or sickly manner.

verb (used with object)

sicklied, sicklying
  1. to cover with a sickly hue.

sickly British  
/ ˈsɪklɪ /

adjective

  1. disposed to frequent ailments; not healthy; weak

  2. of, relating to, or caused by sickness

  3. (of a smell, taste, etc) causing revulsion or nausea

  4. (of light or colour) faint or feeble

  5. mawkish; insipid

    sickly affectation

"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. in a sick or sickly manner

"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

Other Word Forms

Etymology

Origin of sickly

1300–50; Middle English siklich, sekly (adj.). See sick 1, -ly

Explanation

If you're frequently ill, or often under the weather, you're sickly. A sickly child tends to miss a lot of school. Sickly people aren't in perfect health — they are prone to coming down with illnesses, or they just generally don't feel well. You can also describe someone as appearing sickly, if their faces are pale and unhealthy-looking. This "habitually ailing" meaning dates from the fourteenth century, and for a brief time it was also used to mean "causing illness."

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Vocabulary lists containing sickly

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.

Smog compromised the health of kids and the sickly and the elderly.

From Los Angeles Times • Mar. 26, 2026

But the team doesn’t just apply a flattering touch-up to sickly markets.

From The Wall Street Journal • Feb. 14, 2026

Smith was a sickly child, contracting bronchial pneumonia, tuberculosis, German measles, mumps and chicken pox which kept her in "periods of lengthy bed rest".

From BBC • Nov. 4, 2025

Even before ICE got him, he had been sickly.

From Slate • Oct. 27, 2025

He’s pale—not sickly, but like he doesn’t get out in the sun much.

From "Dread Nation" by Justina Ireland

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