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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Antonyms & Near Antonyms
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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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

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 study, which was published in the journal BMC Cardiovascular Disorders, found that keeping irregular bedtimes dramatically raises the risk of major adverse cardiovascular events like heart attack and stroke. —Korin Miller, SELF, 7 Apr. 2026 Most recently, Self missed KU’s game this season against Colorado due to AFib, which is an irregular heartbeat. —Shreyas Laddha, Kansas City Star, 6 Apr. 2026
Noun
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 Turkish troops then began shelling Kurdish towns in Syria, and Turkish forces pushed forward, irregulars executing people in ditches along the road. —Time, 14 Nov. 2019 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
  • In the United States, officials predict a severe fire season in the West at the beginning of the summer, as every state except Michigan and North Dakota is experiencing some level of drought or abnormal dryness.
    — CBS News, CBS News, 15 Apr. 2026
  • Injections of local anesthetics, such as Lidocaine, into the muscles or joints can reduce irritation, muscle spasms and abnormal nerve activities that result in pain.
    — Dr. Patricia Richard, Hartford Courant, 14 Apr. 2026
Definition of abnormal
Adjective
  • Did Curry and Kristaps Porzingis magically turn into Magic and Worthy in their sporadic handful of minutes together this month?
    — Dieter Kurtenbach, Mercury News, 13 Apr. 2026
  • Spears was released from her 13-year conservatorship in 2021 and has largely kept a low profile since then, outside of some sporadic social media activity.
    — Jack Dunn, Variety, 12 Apr. 2026
Definition of sporadic
Adjective
  • However, boundaries have not been redrawn since the 1971 census, as successive governments delayed the process over concerns about uneven population growth.
    — ABC News, ABC News, 16 Apr. 2026
  • Inspired by director Daniel Blake Schwartz’s real-life experiences, this striking debut feature charts the uneven cycles of addiction and recovery among several interconnected lives in Chelsea, Massachusetts with grit and emotional clarity.
    — Ryan Lattanzio, IndieWire, 16 Apr. 2026
Definition of uneven
Adjective
  • Though Fleury turned over the net to Gustavsson and Wallstedt on the ice, the 41-year-old with the second-most wins in NHL history has stayed around the team this season as a practice goalie and with an informal front office role as a player development advisor.
    — CBS News, CBS News, 15 Apr. 2026
  • The site plan for 1st Street Farms includes a range of outdoor amenities such as a multi-use turf field designed for youth sports and community programming, landscaped gardens and walking paths, and open green space for informal recreation and seasonal events.
    — Jessica Alvarado Gamez, Denver Post, 15 Apr. 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
  • Advertisement Hezbollah maintained guerrilla-style warfare against Israel throughout the occupation of southern Lebanon up until 2000, when Israel withdrew from the country.
    — Callum Sutherland, Time, 10 Apr. 2026
  • García said mining areas in Bolívar state remain under the control of organizations such as gangs such as Tren de Aragua and Tren de Guayana and ELN guerrillas, which operate across different mines and control workers, transport routes and processing centers.
    — Antonio María Delgado, Miami Herald, 9 Apr. 2026
Definition of guerrilla
Adjective
  • One of the most unnatural things astronauts have experienced is being on the dark side of the Moon and unable to see Earth.
    — Richard Edwards, Space.com, 19 Apr. 2026
  • The words feel heavy and unnatural when O'Neal repeats them back to the doctor, like trying to blow a bubble and spitting out rocks instead.
    — Courtney Crowder, USA Today, 10 Apr. 2026
Definition of unnatural
Adjective
  • Journalists in the bubble get the pope’s speeches ahead of time and have occasional access to delegation members, as well as other information in real time from the Vatican spokesman.
    — ABC News, ABC News, 16 Apr. 2026
  • Electric Bleu is French food caressed with California seasonality and the occasional pop of Aussie nostalgia.
    — Jenn Harris, Los Angeles Times, 16 Apr. 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 21 Apr. 2026.

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Nglish: Translation of irregular for Spanish Speakers

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