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Showing results for improper.
Definitions

improper

[im-prop-er] / ɪmˈprɒp ər /
ADJECTIVE
not suitable
Synonyms
STRONGEST
awkward erroneous false ill-advised imprudent inaccurate inadmissible inappropriate incorrect irregular unwarranted wrong
WEAK
abnormal at odds bad form discordant discrepant ill-timed inadvisable inapplicable inapposite inapt incongruous inexpedient infelicitous inharmonious inopportune ludicrous malapropos odd off-base out of place out-of-season preposterous unapt unbefitting uncalled-for uncomely undue unfit unfitting unseasonable unsuitable unsuited untimely
Antonyms
STRONGEST
OK acceptable accurate appropriate correct honest reasonable right suitable true valid wise
WEAK
de rigueur decent fitting formal good moral proper uncorrupt
ADJECTIVE
vulgar, immoral
Synonyms
STRONGEST
indecent unethical unjust unseemly untoward wrong wrongful
WEAK
blue dirty impolite indecorous indelicate lewd malodorous naughty risqué rough salacious suggestive unbecoming unconventional unequitable ungodly unrighteous unrightful
Antonyms
STRONGEST
acceptable appropriate decent ethical fair good honest just moral proper right suitable
WEAK
correct fitting formal uncorrupt

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

This regulation is critical because improper activation of LypABC can be highly toxic to bacterial cells.

From Science Daily • Apr. 17, 2026

In October 2025, Organon CEO Kevin Ali resigned after an internal board investigation found what the drugmaker called improper sales practices aimed at boosting quarterly results in recent years.

From Barron's • Apr. 10, 2026

"It is illegal and improper because there is no risk of him fleeing or avoiding questioning," he said.

From BBC • Mar. 27, 2026

Other suspected fraud schemes involve enrolling beneficiaries without their consent and improper billing practices.

From MarketWatch • Mar. 24, 2026

Not all of these were improper requests; but the others were mainly favors, to be done when I had spare time, which was seldom.

From "Newjack: Guarding Sing Sing" by Ted Conover

Vocabulary lists containing improper

CTE Construction ("Core Curriculum: Introductory Craft Skills,") Vocabulary from Module One

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im-

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Way Off: Synonyms for "Wrong"

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