IRREGULAR Synonyms: 265 Similar and Opposite Words

Q: 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

Q: 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

Q: 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

irregular 1 of 2

adjective

i-ˈre-gyə-lər

Definition of irregular

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

Relevance

Antonyms & Near Antonyms

as in sporadic

lacking in steadiness or regularity of occurrence irregular mail delivery to the island

Synonyms & Similar Words

Antonyms & Near Antonyms

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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Antonyms & Near Antonyms

as in informal

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

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Antonyms & Near Antonyms

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

Related Words

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

The length of a day according to UTC is close to that of UT1 but not exactly the same because our planet’s rotation is irregular. — Emma Gometz, Scientific American, 15 Oct. 2026 Each is almost seven by five feet, and most establish a broad field of color—blue, crimson, orange—across which migrate sharp and irregular shapes, some like long teeth or spears, others like shards of obsidian. — Zachary Fine, New Yorker, 14 Oct. 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

Adjective

Infected animals will eventually show signs of abnormal behavior, weight loss and physical debilitation in later stages of the disease.

— DeJanay Booth-Singleton, CBS News, 21 Oct. 2026
The abnormal warmth is also delaying the changing of many tree leaves, and could bring health implications for plants across the Midwest and certain organisms living in the Great Lakes.

— Finnegan Belleau, Chicago Tribune, 21 Oct. 2026

Definition of abnormal

Adjective

In the absence of regular data, analysts and activists interested in immigration trends have relied on information obtained through lawsuits or limited and sporadic information released by federal agencies to track deportation data.

— Rebecca Santana, Los Angeles Times, 22 Oct. 2026
Only some regional operators have continued sporadic services, generally using smaller feeder vessels.

— Lee Ying Shan, CNBC, 16 Oct. 2026

Definition of sporadic

Adjective

The brand's signature technology combines a retinoid with lactic acid to smooth fine lines, uneven tone, and rough texture, and its AlphaRet Exfoliating Peel Pads take things a step further.

— Christa Joanna Lee, Allure, 21 Oct. 2026
These accounts often waive monthly fees without a minimum balance and offer larger transaction or cash deposit allowances, since nonprofits may see uneven cash flow tied to grant cycles and fundraising.

— Andreina Rodriguez, CNBC, 21 Oct. 2026

Definition of uneven

Adjective

Not surprisingly, Bassetti during his informal conversation discussed the benefits of scale in today’s international TV business.

— Etan Vlessing, HollywoodReporter, 19 Oct. 2026
However, this is a far cry from earlier times when lawmakers met regularly, participated in spirited and substantive policy discussions, enjoyed informal dinners and even carpooled back home during congressional breaks.

— John T. Shaw, Chicago Tribune, 18 Oct. 2026

Definition of informal

Noun

Another item removed was a campaign poster of Carlos Pizarro, a former leader of the M-19, a guerrilla movement that signed a peace agreement with the government in March 1989, in which its leaders were pardoned for kidnappings and other war crimes.

— ABC News, ABC News, 19 Oct. 2026
The indictment also describes the detention of a Venezuelan military officer in 2013 who was transported to a camp controlled by Colombia’s FARC guerrilla organization.

— Antonio María Delgado, Miami Herald, 15 Oct. 2026

Definition of guerrilla

Adjective

Some movements feel unnatural, facial expressions are exaggerated, and small details occasionally fall into the uncanny valley or break rules of logical consistency.

— Britta Miller, The Washington Examiner, 14 Oct. 2026
But closer examination reveals that OpenAI’s proof builds its unnatural force in a totally distinct way.

— Joseph Howlett, Scientific American, 13 Oct. 2026

Definition of unnatural

Adjective

The New Braunfels, Texas, resident kept a frenetic touring schedule, headlining major Texas venues and mid-sized dance halls around the country, with occasional arena or amphitheater stops opening for Koe Wetzel thrown in.

— Josh Crutchmer, Rolling Stone, 25 Oct. 2026
That could make removing space junk a routine service rather than an occasional experiment.

— Kurt Knutsson, FOXNews.com, 25 Oct. 2026

Definition of occasional

Cite this Entry

Style

“Irregular.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/irregular. Accessed 27 Oct. 2026.

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Synonyms of irregular

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noun

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Synonyms of irregular

adjective

noun

Synonym Chooser

Example Sentences

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