improper

adjective im·prop·er \(ˌ)im-ˈprä-pər\

: not correct

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

: not suitable for the situation : not appropriate

Full Definition of IMPROPER

: 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>

— im·prop·er·ly adverb

— im·prop·er·ness noun

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Origin of IMPROPER

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

First Known Use: 15th century

Related to IMPROPER

Synonyms: amiss, graceless, inappropriate, inapposite, inapt, incongruous, incorrect, indecorous, inept, infelicitous, malapropos, perverse, unapt, unbecoming, unfit, unhappy, unseemly, unsuitable, untoward, wrong

Antonyms: appropriate, becoming, befitting, correct, decorous, felicitous, fit, fitting, genteel, happy, meet, proper, right, seemly, suitable

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>.