im·​prop·​er (ˌ)im-ˈprä-pər How to pronounce improper (audio)
: not proper: such as
: not in accord with propriety, modesty, good manners, or good taste
improper language
: not suited to the circumstances, design, or end
improper medicine
: not regularly or normally formed or not properly so called
: not in accord with fact, truth, or right procedure : incorrect
improper inference
improperly adverb
improperness noun
Choose the Right Synonym for improper

indecorous, improper, unseemly, unbecoming, indelicate mean not conforming to what is accepted as right, fitting, or in good taste.

indecorous suggests a violation of accepted standards of good manners.

indecorous behavior

improper applies to a broader range of transgressions of rules not only of social behavior but of ethical practice or logical procedure or prescribed method.

improper use of campaign contributions

unseemly adds a suggestion of special inappropriateness to a situation or an offensiveness to good taste.

remarried with unseemly haste

unbecoming suggests behavior or language that does not suit one's character or status.

conduct unbecoming to an officer

indelicate implies a lack of modesty or of tact or of refined perception of feeling.

indelicate expressions for bodily functions

Example Sentences

The doctor gave him an improper diagnosis. They claim to have evidence of improper police conduct. improper use of public land This is an improper diet for a growing teenager. It would be improper for me to ask such a favor of her. He made some improper remarks. See More
Recent Examples on the Web Federal prosecutors have been investigating potentially improper communications between representatives of the companies before Digital World’s listing last October and the unusual trading in Digital World securities before the merger announcement., 23 Nov. 2022 Some Democrats assert that Mr. Trump’s 2016 election was aided by improper foreign interference online, notably through the spreading of fake news on Facebook. John D. Mckinnon, WSJ, 23 Nov. 2022 This report makes 43 recommendations to change police culture, vetting and complaints procedures, including setting minimum standards for prospective officers’ preemployment checks and defining improper behavior at the national level. Annabelle Timsit, Washington Post, 22 Nov. 2022 The state argued it is allowed to access the records to investigate three consumer complaints that accuse Bernard of improper care. Arleigh Rodgers, Chicago Tribune, 22 Nov. 2022 The lawsuit states that the daughter has also incurred costs and sought alternative health insurance because of previous improper denials of coverage by the defendants. Patrick Whittle, ajc, 22 Nov. 2022 Others accused of improper behavior were less warmly embraced. Scott Feinberg, The Hollywood Reporter, 21 Nov. 2022 The driver was charged with misdemeanor death by motor vehicle, careless and reckless, improper equipment, unsafe movement and carrying a firearm in a parade, police said. Grace Hauck, USA TODAY, 19 Nov. 2022 The driver cooperated with detectives and has been charged with misdemeanor death by motor vehicle, careless and reckless, improper equipment, unsafe movement, and carrying a firearm in a parade. Minyvonne Burke, NBC News, 19 Nov. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'improper.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History


Middle English, from Middle French impropre, from Latin improprius, from in- + proprius proper

First Known Use

15th century, in the meaning defined above

Time Traveler
The first known use of improper was in the 15th century

Dictionary Entries Near improper

Cite this Entry

“Improper.” Dictionary, Merriam-Webster, Accessed 26 Nov. 2022.

Kids Definition



im·​prop·​er (ˈ)im-ˈpräp-ər How to pronounce improper (audio)
: not proper, right, or suitable
improperly adverb

Legal Definition



: not proper: as
: not in accord with correct procedure
an improper venue
: wrongful
specifically : in violation of a constitution
the denial of trial by jury was held improper
improperly adverb

More from Merriam-Webster on improper

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