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.

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abnormal British  

/ æbˈnɔːməl /

adjective

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

2. informal odd in behaviour or appearance; strange

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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

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.

Example Sentences

The Masters will never be as famous as the British Open for rain-soaked afternoons, yet it’s abnormal for conditions to be this dry.

From The Wall Street Journal • Apr. 11, 2026

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

The cancerous plasma cells produce large amounts of an abnormal antibody called M protein, which builds up in bone marrow and forms tumors in bones, like the one in my hip.

From Slate • Mar. 29, 2026

Flames of abnormal size were pursuing them, licking up the sides of the junk bulwarks, which were crumbling to soot at their touch.

From "Harry Potter and the Deathly Hallows" by J.K. Rowling

Related Words

• aberrant
• anomalous
• atypical
• bizarre
• exceptional
• extraordinary
• irregular
• odd
• peculiar
• strange
• uncommon
• unexpected
• unnatural
• unusual
• weird