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adjective im·prop·er \(ˌ)im-ˈprä-pər\

Simple Definition of improper

  • : not correct

  • : not following rules of acceptable behavior : legally or morally wrong

  • : not suitable for the situation : not appropriate

Source: Merriam-Webster's Learner's Dictionary

Full Definition of improper

  1. :  not proper: as a :  not in accord with fact, truth, or right procedure :  incorrect <improper inference> b :  not regularly or normally formed or not properly so called c :  not suited to the circumstances, design, or end <improper medicine> d :  not in accord with propriety, modesty, good manners, or good taste <improper language>

improperly adverb
improperness noun

Examples of improper in a sentence

  1. The doctor gave him an improper diagnosis.

  2. They claim to have evidence of improper police conduct.

  3. improper use of public land

  4. This is an improper diet for a growing teenager.

  5. It would be improper for me to ask such a favor of her.

  6. He made some improper remarks.

Origin of improper

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

First Known Use: 15th century

Synonym Discussion of 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>.

IMPROPER Defined for Kids


adjective im·prop·er \im-ˈprä-pər\

Definition of improper for Students

  1. :  not proper, right, or suitable <He used improper grammar.>

improperly adverb

Law Dictionary


adjective im·prop·er

Legal Definition of improper

  1. :  not proper: as a :  not in accord with correct procedure <an improper venue> b :  wrongful; specifically :  in violation of a constitution <the denial of trial by jury was held improper>

improperly adverb

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