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abnormal

adj. · n.
US //æbˈnɔɹməɫ// UK //ɐbnˈɔːməl// ab·nor·mal
  1. 1 unusual or irregular (adj.)
    B2 Upper Intermediate

    different from what is normal or expected, especially in a way that is not good.

    deviating from a standard, rule, or typical pattern; often used in technical or medical contexts to describe results outside the expected range.

    Example

    The doctor said the test results were abnormal and ordered more scans.

    Example

    The meteorological station recorded abnormal temperature fluctuations throughout the month, suggesting a significant shift in regional climate patterns.

    Usage

    Often used to describe data, physical conditions, or weather patterns.
  2. 2 socially or mentally unusual (adj.)
    C1 Advanced Formal

    behaving in a way that is not considered social or healthy by most people.

    pertaining to behaviour that deviates from social norms or accepted standards of psychological health.

    Example

    The suspect showed abnormal behaviour during the police interview.

    Example

    Psychologists noted that the subject's abnormal reactions to social stimuli were consistent with a rare neurological condition.

    Teacher's tip

    In modern social contexts, this can sound judgmental; 'atypical' or 'unconventional' are often softer alternatives.
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  1. 3 an unusual person or thing (n.)
    C2 Proficiency Formal Archaic

    a person or thing that is not normal.

    an individual or object that deviates from the norm; used as a substantive noun.

    Example

    In this group of healthy plants, this stunted one is an abnormal.

    Example

    The researcher categorised the outliers as abnormals to be studied separately from the control group.

    Usage

    Rarely used as a noun in modern English; usually functions as an adjective.
Origin

From ab- + normal. First attested in 1835, replacing the earlier anormal and even earlier abnormous, from Latin abnormis (“departing from normal”), from either ab- (“away from”) + norma (“rule, norm”), or Ancient Greek ἀνώμαλος (anṓmalos).

Word family

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