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

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Relevance

Antonyms & Near Antonyms

as in sporadic

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

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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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as in informal

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

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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

Rather, those with irregular or unpredictable incomes just have to approach the budgeting process a bit differently than those with steady paychecks. — Becca Stanek, TheWeek, 26 Aug. 2026 That included decreased risk of heart disease, heart failure and atrial fibrillation, or irregular heart rhythm. — Sara Moniuszko, USA Today, 26 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

Adjective

Department staff searched for the otter to assess whether the animal was still in the area or displaying any abnormal or concerning behavior, Margiott said.

— Karen Garcia, Los Angeles Times, 3 Sep. 2026
An abnormal increase in a protein called sFlt-1 (soluble fms-like tyrosine kinase 1), which slows down placental growth, Kilpatrick says.

— Megha Satyanarayana, Scientific American, 2 Sep. 2026

Definition of abnormal

Adjective

Bahrain and Kuwait, which have continued to face sporadic Iranian attacks, will have the lowest staffing of the Gulf embassies, with three-quarters of Foreign Service members returning.

— Shelby Talcott, semafor.com, 26 Aug. 2026
Attacks on Kenscoff have escalated The first major attack on Kenscoff occurred in January 2025, and since then, there have been sporadic attacks in the mountains surrounding the city center.

— Pierre-Richard Luxama, Los Angeles Times, 25 Aug. 2026

Definition of sporadic

Adjective

That is an unusually light amount of in-game preparation for a second-year quarterback learning a new offense, especially since Dart and the offense have had an uneven summer at best.

— Pat Leonard, New York Daily News, 29 Aug. 2026
Together, these findings pointed to uneven conditions beneath the road.

— Rupendra Brahambhatt, Interesting Engineering, 29 Aug. 2026

Definition of uneven

Adjective

On paper, the January agreement between Damascus and the SDF provides a framework for resolving informal wartime boundaries and closed routes and for harmonizing competing duties and parallel systems of governance.

— Jesse Marks, Foreign Affairs, 31 Aug. 2026
The minimum monthly salary for a state worker in Cuba is 3,210 pesos, currently less than $5 in the informal dollar exchange market.

— Nora Gámez Torres, Miami Herald, 31 Aug. 2026

Definition of informal

Adjective

The difference is not the map, but how changing conditions are interpreted along the way.

— Alex Shahidi, Forbes.com, 21 Aug. 2026
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

But Bernard’s move is a gambit, meant to create a distraction while the Mechanical guerrillas set off dynamite charges in the mines, for reasons as yet unrevealed.

— Noel Murray, Vulture, 28 Aug. 2026
There may be as many as 200,000 in this army, waiting for orders to launch a guerrilla war.

— Danielle Parker, CBS News, 28 Aug. 2026

Definition of guerrilla

Adjective

There are occasional non-permanent exhibitions relating to architecture and design.

— Condé Nast, Condé Nast Traveler, 1 Sep. 2026
Their Conan is the host for the Oscars, a podcast host, a voice in Toy Story 5, a world traveler, an occasional actor, and many other things.

— Emily Palmer Heller, Vulture, 1 Sep. 2026

Definition of occasional

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Style

“Irregular.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/irregular. Accessed 4 Sep. 2026.

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Synonyms of irregular

adjective

noun

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Synonyms of irregular

adjective

noun

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