undesirable

1 of 2

adjective

un·​de·​sir·​able ˌən-di-ˈzī-rə-bəl How to pronounce undesirable (audio)
Synonyms of undesirable
: not desirable : unwanted
undesirable side effects
undesirability
ˌən-di-ˌzī-rə-ˈbi-lə-tē How to pronounce undesirable (audio)
noun
undesirableness
ˌən-di-ˈzī-rə-bəl-nəs How to pronounce undesirable (audio)
noun
undesirably
ˌən-di-ˈzī-rə-blē How to pronounce undesirable (audio)
adverb

undesirable

2 of 2

noun

: one that is undesirable

Examples of undesirable in a Sentence

Adjective The drug has some undesirable side effects. This may have undesirable consequences. Frankly, it's an undesirable and unpleasant job.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Adjective
OpenAI found that its monitoring systems would be less likely to detect when its new Astra model behaves in undesirable ways through chain-of-thought compared to older models, according to documentation from early September. — Lisa Eadicicco, CNN Money, 16 Oct. 2026 Previously considered an undesirable byproduct, these structures have displayed unusual optical properties, including the ability to polarize, refract, and conduct light in distinctive ways. — Kaif Shaikh, Interesting Engineering, 13 Oct. 2026
Noun
And so our ward, New Hyde, becomes a sort of metaphor for all the ways in which society disappears its undesirables. — John Hopewell, Variety, 27 Apr. 2026 The undesirables who entered our country illegally, then committed some crime, were defended by protests against federal law enforcement. — Roger Van Zanen, The Orlando Sentinel, 17 Feb. 2026 See All Example Sentences for undesirable

Word History

First Known Use

Adjective

1667, in the meaning defined above

Noun

1883, in the meaning defined above

Time Traveler
The first known use of undesirable was in 1667

Rhymes for undesirable

See All Rhymes for undesirable

Browse Nearby Words

undesirability
undesirable
undesirable discharge
See all Nearby Words

Cite this Entry

“Undesirable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undesirable. Accessed 20 Oct. 2026.

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Kids Definition

undesirable

adjective
un·​de·​sir·​able
ˌən-di-ˈzī-rə-bəl
: not desirable : unwanted
undesirability
-ˌzī-rə-ˈbil-ət-ē
noun
undesirable noun
undesirableness
-ˈzī-rə-bəl-nəs
noun
undesirably
-blē
adverb

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