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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

Related Words

See irregular.

Other Word Forms

  • abnormally adverb
  • abnormalness noun
  • superabnormal adjective
  • superabnormally adverb

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

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.

High potassium levels can lead to abnormal heart rhythms.

From Science Daily • Mar. 31, 2026

This month, the zoo announced Tina was suffering from an infection and abnormal buildup of fluid in her uterus.

From Los Angeles Times • Mar. 31, 2026

"This is abnormal, for sure," says Mukesh Sahdev, chief oil analysts at XAnalysts.

From BBC • Mar. 24, 2026

Tedros said the International Atomic Energy Agency was looking into the strikes, and "no indications of abnormal or increased off-site radiation levels have been reported".

From Barron's • Mar. 22, 2026

In the New Orleans show, I felt all the amusement of the improbable abnormal, but also a kind of horror that it could be so.

From "Travels with Charley in Search of America" by John Steinbeck

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.