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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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

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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

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

Until recently, diagnosing Alzheimer’s required a medical history and exam as well as postmortem evidence of two abnormal proteins associated with the disease called amyloid and tau.

— Anand Kumar, The Conversation, 26 Aug. 2026
The audit assistance tool, now a requirement by Flock Safety, flags abnormal use by officers.

— Mark Morales, CNN Money, 26 Aug. 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

Currently, informal waste pickers and scrap collectors make up a large portion of Vietnam’s collection system, so the new policy also will factor in that labor so that workers aren’t left behind.

— Jennifer Bringle, Footwear News, 25 Aug. 2026
Jeffries met privately with Kushner, a powerful but informal adviser to Trump, several weeks ago.

— Dave Goldiner, New York Daily News, 25 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

Her parents refuse to see that there is something unnatural about their new baby boy and that an evil other presence haunts their stately home.

— Tanya Fedak, Variety, 26 Aug. 2026
The researchers say the approach could help overcome limitations of existing humanoid control systems, which often require extensive fine-tuning or produce rigid, unnatural movements.

— Jijo Malayil, Interesting Engineering, 26 Aug. 2026

Definition of unnatural

Adjective

When Russia invaded Ukraine in early 2022, her family spent months in a bomb shelter, risking only occasional visits back to their apartment.

— Josh Bergeron, Charlotte Observer, 25 Aug. 2026
The Sox entered Tuesday ranked last in the majors with 561 innings pitched by starters — a number impacted in part by their occasional use of an opener.

— LaMond Pope, Chicago Tribune, 25 Aug. 2026

Definition of occasional

Cite this Entry

Style

“Irregular.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/irregular. Accessed 2 Sep. 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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