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Synonyms

abnormal

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

adjective

  1. An image of the word abnormal as defined by not normal, average, typical, or usual; deviating from a standard.

    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.

See Examples For:

She had routine surgery for craniosynostosis, external, a birth defect affecting the skull, but an abnormal chest X-ray was not flagged.

From BBC ● Oct. 31, 2026

The biomarker remained significantly associated with cognitive impairment even after researchers accounted for amyloid-beta plaques, which are abnormal protein deposits in the brain that can be detected with PET imaging.

From Science Daily ● Oct. 31, 2026

Traditionally, much of the field has focused on understanding the processes that damage the brain, including the accumulation of abnormal proteins and the loss of neurons.

From Science Daily ● Oct. 27, 2026

Tumors carry mutations that can produce abnormal proteins the immune system can recognize.

From The Wall Street Journal ● Oct. 24, 2026

Though he has become rather proficient at slipping in at abnormal hours, sneaking out is a different matter.

From "The Night Circus" by Erin Morgenstern

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