improper

[im-prop-er]

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

/ 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

Other Word Forms

• improperly adverb
• improperness noun

Word History and Origins

Origin of improper¹

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

Synonym Study

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.

Example Sentences

Legally speaking, you can contest a will or trust due to lack of testamentary capacity, undue influence from a family member, fraud, coercion, improper execution or if there was a newer will in existence.

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The court's reliance on this shadow docket has been criticised by left-leaning legal scholars and politicians as an improper use of the court's authority.

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Sephora, shoppers’ go-to spot for celebrity makeup brands and skincare essentials, is facing a hefty fine from California cities for alleged improper disposal of its leftover products.

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In December 2023, the California Rifle and Pistol Assn. sued the Sheriff’s Department over what it alleged were improper delays and rejections of applications for concealed carry licenses.

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Prosecutors had sought an arrest warrant for Han on four charges including improper solicitation and graft, and occupational embezzlement.

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Related Words

• awkward 
• erroneous 
• false 
• ill-advised 
• imprudent 
• inaccurate 
• inadmissible 
• inappropriate 
• incorrect 
• irregular 
• unwarranted 
• wrong 

When To Use

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.