irregular 1 of 2

adjective

i-ˈre-gyə-lər How to pronounce irregular (audio)
Definition of irregularnext
1
as in abnormal
departing from some accepted standard of what is normal it was a bank customer's slightly irregular behavior that made people suspicious

Synonyms & Similar Words

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Antonyms & Near Antonyms
2
as in sporadic
lacking in steadiness or regularity of occurrence irregular mail delivery to the island

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Antonyms & Near Antonyms
3
as in uneven
not having a level or smooth surface although the moon looks smooth from here, it actually has a very bumpy and irregular surface

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4
as in informal
not rigidly following established form, custom, or rules the request is irregular, but I'll allow it

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5
as in changing
not staying constant irregular gusts of wind

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Antonyms & Near Antonyms

irregular

2 of 2

noun

as in guerrilla

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Dissimilar Words

Synonym Chooser

How is the word irregular distinct from other similar adjectives?

The words anomalous and unnatural are common synonyms of irregular. While all three words mean "not conforming to rule, law, or custom," irregular implies not conforming to a law or regulation imposed for the sake of uniformity in method, practice, or conduct.

concerned about his irregular behavior

When would anomalous be a good substitute for irregular?

Although the words anomalous and irregular have much in common, anomalous implies not conforming to what might be expected because of the class or type to which it belongs or the laws that govern its existence.

her drive made her an anomalous figure in a sleepy organization

When could unnatural be used to replace irregular?

The meanings of unnatural and irregular largely overlap; however, unnatural suggests what is contrary to nature or to principles or standards felt to be essential to the well-being of civilized society.

prisoners treated with unnatural cruelty

Example Sentences

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.
Recent Examples of irregular
Adjective
Ramírez, only 22, has thrived in his first taste of the majors while making the most of his irregular playing time. — Meghan Montemurro, Chicago Tribune, 5 Aug. 2026 In a 2025 randomized trial of 100 overweight and obese women with PMOS and irregular menstrual cycles, adding semaglutide to metformin for 16 weeks restored their cycles in 73% of participants, compared with 42% on only metformin. — Jesse Pines, Forbes.com, 4 Aug. 2026
Noun
As fighting raged in 1948 between Arab armies, Palestinian irregulars and Zionist forces, Mariam and her family fled to a Palestinian farming village, Umm al-Fahem. — Isabel Kershner, BostonGlobe.com, 22 July 2023 As volunteer companies were raised to drive out the Mexican forces — who were occupying their own country — some of the irregulars were joined by free black men. — Paula Allen, ExpressNews.com, 15 Feb. 2020 See All Example Sentences for irregular
Recent Examples of Synonyms for irregular
  1. abnormal
  2. sporadic
  3. uneven
  4. informal
  5. changing
  6. guerrilla
  7. unnatural
  8. occasional
Adjective
  • Combine this wanderlust with increasingly abnormal weather patterns and rapidly warming ocean waters, and sightings of these tropical birds can increase.
    — Laura Baisas, Popular Science, 6 Aug. 2026
  • Wild week Mize did not acknowledge how abnormal the past six or seven days have been until he was asked about it a couple times following last night’s game.
    — Kevin Acee, San Diego Union-Tribune, 6 Aug. 2026
Definition of abnormal
Adjective
  • Sporadic attacks risk largely blocking the waterway In the Strait of Hormuz, Iran has shown that even sporadic attacks on ships can be enough to effectively close a critical waterway by driving up risks and insurance premiums.
    — Fatma Khaled, Chicago Tribune, 8 Aug. 2026
  • The Strait of Hormuz — which handled around one-fifth of global oil supply before the war — has seen traffic drop to a trickle with sporadic increase in ship transits on positive headlines.
    — Anniek Bao, CNBC, 3 Aug. 2026
Definition of sporadic
Adjective
  • Bohm has endured an uneven campaign, showcasing both encouraging offense and periods of struggle, raising concerns about his viability in a contract year.
    — Peter Chawaga, Forbes.com, 9 Aug. 2026
  • Fans of celebrity bald eagle Jackie are again grappling with troubling news about her health, the latest downturn in an uneven recovery since her rescue near Big Bear Lake last month.
    — Lila Seidman, Los Angeles Times, 8 Aug. 2026
Definition of uneven
Adjective
  • The service Low-key and informal with free-roaming check-in staff.
    — Condé Nast, Condé Nast Traveler, 4 Aug. 2026
  • From the outside, the leadership style can appear overly gentle, patient or informal.
    — Jessica Hill Holm, Forbes.com, 4 Aug. 2026
Definition of informal
Adjective
  • In some studies, gloves not changed between tasks had higher bacterial counts and could transfer germs just as easily as ungloved hands, underscoring the need for frequent changing and proper hand hygiene.
    — Evan Moore December 19, Charlotte Observer, 19 Dec. 2025
Definition of changing
Noun
  • Kim Il-Sung The dynasty originated with Kim Il-Sung, a Korean guerrilla leader who fought against Japanese colonial rule during the 1930s and later served as an officer in the Soviet Red Army during World War II.
    — Ethan Teekah, Encyclopedia Britannica, 6 Aug. 2026
  • Then, the guerilla activists left a final letter pinned to the door of a government office later that year, stating that their aims had been met.
    — RJ Mackenzie, Popular Science, 5 Aug. 2026
Definition of guerrilla
Adjective
  • The PlayStation Move Motion controllers put the power in your hands and give you the freedom to control every move in-game without the unnatural feeling of a traditional controller.
    — BestReviews, Mercury News, 5 Aug. 2026
  • This is a standard procedure for unnatural deaths in Jackson County, not necessarily an indication that a crime was committed or is suspected.
    — James Powel, USA Today, 22 July 2026
Definition of unnatural
Adjective
  • Today, Armstrong's two-story boyhood home is an occasional stop for visitors of the Armstrong Air and Space Museum in Wapakoneta, even though the house itself isn't open for tours.
    — ABC News, ABC News, 5 Aug. 2026
  • Prioritizing water most of the time and enjoying diet or sugar-free soda as an occasional treat can support good health.
    — Lindsey DeSoto, HEALTH, 4 Aug. 2026
Definition of occasional

Browse Nearby Words

irrefutable
irregular
irregularities
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Cite this Entry

“Irregular.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/irregular. Accessed 11 Aug. 2026.

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