improper

adjective

im·​prop·​er (ˌ)im-ˈprä-pər 

: not proper: such as

a

: not in accord with propriety, modesty, good manners, or good taste

improper language

b

: not suited to the circumstances, design, or end

improper dress/attire

an improper diet

an improper diagnosis

c

: not regularly or normally formed or not properly so called

d

: not in accord with fact, truth, or right procedure : incorrect

improper inference

improper use of public land

specifically : in violation of a constitution

denial of trial by jury was held improper

improperly adverb

improperness noun

Synonyms of improper

• inappropriate
• unsuitable
• incorrect
• wrong
• unfit
• unhappy

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

Examples of improper in a Sentence

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.

Recent Examples on the Web

Studies show that improper or extended use of gloves can actually lead to higher levels of bacterial contamination on gloves than on bare hands, because microbes can accumulate under gloves and give a false sense of security if they aren’t changed regularly. —Evan Moore december 19, Charlotte Observer, 19 Dec. 2025

The complaints claim that due to improper restraint of their head, the guests were repeatedly shaken violently, causing the injuries. —Colson Thayer, PEOPLE, 19 Dec. 2025

In the weeks after the protest, KU’s Student Affairs office initiated disciplinary proceedings against Students for Justice in Palestine and its officers, citing alleged violations that included improper camping, the use of signs attached to sticks, chalking sidewalks and excessive noise. —David Hudnall, Kansas City Star, 18 Dec. 2025

These violations involve conditions that can directly increase the risk of foodborne illness or injury, such as improper food temperatures, cross-contamination or unsafe food handling practices. —Rey Covarrubias Jr, AZCentral.com, 18 Dec. 2025

Word History

Etymology

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

First Known Use

15th century, in the meaning defined above

Phrases Containing improper

• improper fraction
• improper integral

Rhymes for improper

• eavesdropper
• grasshopper
• leafhopper
• sharecropper
• chopper
• copper
• cropper
• dropper
• pauper
• popper
• proper
• shopper

Kids Definition

improper

adjective

im·​prop·​er (ˈ)im-ˈpräp-ər 

: not proper, right, or suitable

improperly adverb

Legal Definition

improper

adjective

im·​prop·​er

: 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