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Synonyms

abnormal

American  
[ab-nawr-muhl] / æbˈnɔr məl /

adjective

  1. not normal, average, typical, or usual; deviating from a standard.

    abnormal powers of concentration; an abnormal amount of snow; abnormal behavior.

    Synonyms:
    odd, unnatural, deviant, irregular, aberrant, anomalous
  2. extremely or excessively large.

    abnormal profit.


abnormal British  
/ æbˈnɔːməl /

adjective

  1. not normal; deviating from the usual or typical; extraordinary

  2. informal odd in behaviour or appearance; strange

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Synonym Usage

See irregular.

Other Word Forms

Etymology

Origin of abnormal

First recorded in 1850–55; ab- + normal; replacing anormal, from Medieval Latin anōrmālus, variant of anōmālus anomalous, influenced by Latin norma norm

Explanation

If you get a snowstorm in the middle of July, you could say that you are experiencing “abnormal weather.” Something that is abnormal is out of the ordinary, or not typical. Abnormal is a combination of the Latin prefix ab which means “away from,” and the English word normal. It essentially means “not normal,” or "unusual.” Abnormal implies that whatever is “not normal” is also undesirable. However, abnormal is sometimes used in a positive context. The phrase “abnormal intelligence,” for instance, usually refers to someone with especially high intelligence.

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Vocabulary lists containing abnormal

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Abnormal levels of groundwater and soil pollution were detected near a 3M site in Zwijndrecht, outside the port city of Antwerp, in 2021.

From Barron's • Feb. 24, 2026

Abnormal animal behavior is often a sign of infection, like bats flying in the daytime or normally timid creatures interacting with humans.

From Los Angeles Times • Nov. 27, 2024

Abnormal regulation by microRNAs can contribute to cancer and to some conditions including congenital hearing loss and bone disorders.

From BBC • Oct. 7, 2024

Abnormal patterns of sleep and waking activity have been studied as potential early indicators of Alzheimer's.

From Science Daily • Mar. 11, 2024

Lots of Abnormal laughs, served with sprouts on the side, is what!

From "Feed" by M.T. Anderson

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