Synonyms of improper

improper

adjective

(ˌ)im-ˈprä-pər 

as in inappropriate

not appropriate for a particular occasion or situation

an improper use of slang in a formal piece of writing

Synonyms & Similar Words

• inappropriate
• unsuitable
• incorrect
• wrong
• unfit
• unhappy
• irrelevant
• unfortunate
• unseemly
• indecorous
• incongruous
• out of place
• infelicitous
• unbecoming
• unacceptable
• inconsistent
• perverse
• out of the way
• inapt
• inept
• bad
• untoward
• amiss
• unapt
• awkward
• graceless
• inapposite
• untimely
• inopportune
• extraneous
• naughty
• unseasonable
• inapplicable
• malapropos
• incompatible
• forbidden
• immaterial
• sinful
• mismatched
• prohibited
• uncongenial
• unsatisfactory
• irrelative
• censurable
• blameworthy
• ungraceful
• disallowed
• barred
• blamable
• proscribed
• outlawed
• gauche
• banned
• misbecoming
• interdicted

Antonyms & Near Antonyms

• appropriate
• proper
• correct
• suitable
• right
• fitting
• relative
• happy
• meet
• timely
• relevant
• applicable
• becoming
• felicitous
• decorous
• fit
• opportune
• apt
• fortunate
• seasonable
• genteel
• permitted
• compatible
• material
• adequate
• harmonious
• congenial
• pointed
• authorized
• acceptable
• seemly
• pat
• satisfactory
• apposite
• befitting
• endorsed
• approved
• fine
• sanctioned
• decent
• promoted
• licensed
• okay
• supported
• kosher
• all right
• allowed
• tolerable
• respectable
• germane
• exemplary
• OK
• passable
• commendable
• apropos
• creditable
• encouraged
• balanced
• blameless
• consonant
• irreproachable
• abetted
• indorsed
• congruous
• companionate

Synonym Chooser

How does the adjective improper differ from other similar words?

Some common synonyms of improper are indecorous, indelicate, unbecoming, and unseemly. While all these words mean "not conforming to what is accepted as right, fitting, or in good taste," 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

When would indecorous be a good substitute for improper?

The synonyms indecorous and improper are sometimes interchangeable, but indecorous suggests a violation of accepted standards of good manners.

indecorous behavior

When is indelicate a more appropriate choice than improper?

The words indelicate and improper can be used in similar contexts, but indelicate implies a lack of modesty or of tact or of refined perception of feeling.

indelicate expressions for bodily functions

In what contexts can unbecoming take the place of improper?

While in some cases nearly identical to improper, unbecoming suggests behavior or language that does not suit one's character or status.

conduct unbecoming to an officer

When could unseemly be used to replace improper?

The words unseemly and improper are synonyms, but do differ in nuance. Specifically, unseemly adds a suggestion of special inappropriateness to a situation or an offensiveness to good taste.

remarried with unseemly haste

Example Sentences

Recent Examples of improper

At least one child in Michigan died of hepatitis B infection that year, who was missed, according to a CDC MMWR report, due to improper documentation. —Dr. Jade Cobern, ABC News, 18 Sep. 2025

Within a quarter, search times in their collaboration tools dropped by 30%, and security incidents tied to improper access fell to zero. —Expert Panel®, Forbes.com, 18 Sep. 2025

High levels of improper payments made across Medicaid services, which some conservative groups and lawmakers say demonstrate a need to shake up the system and improve efficiency, has become a hot topic. —Jasmine Laws, MSNBC Newsweek, 17 Sep. 2025

In 2024, improper payments added up to $54 billion. —Kurt Knutsson, FOXNews.com, 17 Sep. 2025