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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

Derived 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.

The movie’s title and setting—an endless expanse of deserted, largely furniture-free office space bathed in sickly yellow—come from a crowd-sourced urban legend or “creepypasta” that spread online before the pandemic.

From The Wall Street Journal • May 28, 2026

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

From Los Angeles Times • Mar. 26, 2026

But it’s not wrong that the movement is starting to look a little sickly.

From Salon • Nov. 24, 2025

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

By 1875, when Roosevelt was seventeen years old, he was no longer a timid and sickly child.

From "Death on the River of Doubt" by Samantha Seiple

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