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Synonyms

improper

American  
[im-prop-er] / ɪmˈprɒp ər /

adjective

  1. not proper; not strictly belonging, applicable, correct, etc.; erroneous.

    He drew improper conclusions from the scant evidence.

    Synonyms:
    unfit, unsuited, inapplicable
    Antonyms:
    suitable, fitting
  2. not in accordance with propriety of behavior, manners, etc..

    improper conduct at a funeral.

    Synonyms:
    indecorous, unfit, unsuited, inapplicable
    Antonyms:
    proper
  3. unsuitable or inappropriate, as for the purpose or occasion.

    improper attire for a formal dance.

    Synonyms:
    unfit, unsuited, inapplicable
    Antonyms:
    suitable, fitting
  4. abnormal or irregular.

    improper functioning of the speech mechanism.


improper British  
/ ɪmˈprɒpə /

adjective

  1. lacking propriety; not seemly or fitting

  2. unsuitable for a certain use or occasion; inappropriate

    an improper use for a tool

  3. irregular or abnormal

"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

Usage

What does improper mean? Improper describes something considered unsuitable or inappropriate for the purpose or occasion, as in A ballgown is improper dress for playing basketball.Improper also describes something that isn’t appropriate for a specific scenario or circumstance, as in Shouting out the answers during a silent test is generally considered improper.Improper can also describe something that is not correct, such as with an inaccurate conclusion or faulty language usage.Finally, improper can be used to describe something as abnormal or irregular, particularly in reference to how something mechanical operates.Example: We knew the test readouts were improper because the results were physically impossible.

Related Words

Improper, indecent, unbecoming, unseemly are applied to that which is unfitting or not in accordance with propriety. Improper has a wide range, being applied to whatever is not suitable or fitting, and often specifically to what does not conform to the standards of conventional morality: improper diet; improper behavior in church; improper language. Indecent, a strong word, is applied to what is offensively contrary to standards of propriety and especially of modesty: indecent behavior, literature. Unbecoming is applied to what is especially unfitting in the person concerned: conduct unbecoming a minister. Unseemly is applied to whatever is unfitting or improper under the circumstances: unseemly mirth.

Other Word Forms

  • improperly adverb
  • improperness noun

Etymology

Origin of improper

From the Latin word improprius, dating back to 1535–45. See im- 2, proper

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.

Morgan Gire said “changes in state law and recent parole board failures” led to his improper release.

From Los Angeles Times

“There was nothing improper about Mr. Nelson’s limited interactions with Epstein” after the bank pushed out Epstein as a client, he said.

From The Wall Street Journal

The rule states that there should be no behaviour that is "improper, offensive, violent, threatening, abusive, indecent, insulting or provocative".

From BBC

Critics say shareholder proposals are excessive or misused, but the system includes safeguards that allow companies to exclude proposals that are irrelevant, duplicative, vague or improper.

From The Wall Street Journal

During a pretrial conference Thursday, the judge said at one point that it would be improper for the jury to consider what she would have earned had she stayed at Centerview beyond the three-year program.

From The Wall Street Journal