anom·​a·​lous ə-ˈnä-mə-ləs How to pronounce anomalous (audio)
: inconsistent with or deviating from what is usual, normal, or expected : irregular, unusual
Researchers could not explain the anomalous test results.
: of uncertain nature or classification
an anomalous figure in the world of politics
: marked by incongruity or contradiction : paradoxical
anomalously adverb
anomalousness noun
Choose the Right Synonym for anomalous

irregular, anomalous, unnatural 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

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

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

Examples of anomalous in a Sentence

Researchers could not explain the anomalous test results. that was an anomalous year for the housing industry, so the number of starts is anything but typical
Recent Examples on the Web That anomalous incident notwithstanding, the number of satellites orbiting Earth, commercial and otherwise, is expected to quadruple in the coming years, a dramatic development explored in the new HBO documentary Wild Wild Space, directed by Oscar winner Ross Kauffman (Born into Brothels). Matthew Carey, Deadline, 16 July 2024 Such prolonged heat for consecutive days is quite anomalous for San Diego County, NWS meteorologist Adam Roser told Axios. Kate Murphy, Axios, 9 July 2024 Machine learning algorithms can analyze vast amounts of data to identify anomalous behavior and potential security breaches in real-time, enabling proactive defense measures. Nick Kasmik, USA TODAY, 20 Apr. 2024 Once the anomalous effects of computer industry are excluded, the data offer no obvious evidence that automation has driven the decline in manufacturing employment. Susan N. Houseman, Foreign Affairs, 7 Sep. 2018 See all Example Sentences for anomalous 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'anomalous.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


Late Latin anōmalus "irregular (of grammatical paradigms), unequal in size (of planets)" (borrowed from Greek anṓmalos "not uniform, unequal, inconsistent, irregular [in grammar]," from an- an- + homalόs "even, uniform, equal, like") + -ous — more at similar

First Known Use

1606, in the meaning defined at sense 1

Time Traveler
The first known use of anomalous was in 1606

Dictionary Entries Near anomalous

Cite this Entry

“Anomalous.” Dictionary, Merriam-Webster, Accessed 25 Jul. 2024.

Kids Definition


anom·​a·​lous ə-ˈnäm-ə-ləs How to pronounce anomalous (audio)
: not following a general rule or method : irregular, unusual
anomalously adverb
anomalousness noun

Medical Definition


anom·​a·​lous ə-ˈnäm-ə-ləs How to pronounce anomalous (audio)
: deviating from normal
anomalous development
anomalous pulmonary venous drainagePhysicians' Current Procedural Terminology
specifically : having abnormal vision with respect to a particular color but not color-blind
she was almost red anomalous Nature

More from Merriam-Webster on anomalous

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