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 medicine

c

: not regularly or normally formed or not properly so called

d

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

improper inference

improperly adverb

improperness noun

Synonyms

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

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

Courts and Compliance In terms of the legal battles over Trump's moves, people widely rejected the administration's accusations of improper judicial interference. —Gary Langer, ABC News, 26 Apr. 2025

Graham was arrested shortly before 4:45 p.m. and charged with engaging police in pursuit, operating an unregistered motor vehicle, improper use of a marker plate, operation without minimum insurance, unsafe passing and operating a motor vehicle without a license. —Justin Muszynski, Hartford Courant, 25 Apr. 2025

The number is three times more than in 2023 (12.7 million), and the most common violations included ad network abuse, trademark infringement, improper use of personalized ads, false healthcare and medicine claims, and misrepresentation. —Jibin Joseph, PC Magazine, 16 Apr. 2025

The factors that trigger a suspension usually include ad network abuse, improper use of personalization data, false medical claims, trademark infringement, or a mix of violations. —ArsTechnica, 16 Apr. 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