anomalous

adjective

anom·​a·​lous ə-ˈnä-mə-ləs How to pronounce anomalous (audio)
1
: inconsistent with or deviating from what is usual, normal, or expected : irregular, unusual
Researchers could not explain the anomalous test results.
2
a
: of uncertain nature or classification
an anomalous figure in the world of politics
b
: 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
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.
Monitor for continued anomalous requests — particularly from Tencent, AWS, and other cloud provider ASNs. Tony Bradley, Forbes.com, 29 June 2025 While this Iranian response appeared largely symbolic, the country could seek to hit at the U.S. in more anomalous ways, such as by targeting American diplomatic, consular or trade missions. Ellen Mitchell, The Hill, 24 June 2025 But that year does look a little anomalous on his career ledger, with more of an 80-point baseline (which, of course, is still excellent). Max Bultman, New York Times, 17 June 2025 Norton’s similar feature specifically watches for anomalous events such as charges that don’t fit your patterns. PC Magazine, 17 June 2025 See All Example Sentences for anomalous

Word History

Etymology

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

Cite this Entry

“Anomalous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/anomalous. Accessed 4 Jul. 2025.

Kids Definition

anomalous

adjective
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

anomalous

adjective
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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