improper

Improper words and actions are inappropriate. They're not suited to the occasion or done in polite company. They’re just not proper!

Surprise! Improper is the opposite of proper. Something that’s improper goes against what people think is right. This could be a matter of politeness. For example, not giving up your seat for an elderly person is improper. Or it could be more serious, like going to school with no pants on. It could also be something uncool like meeting your best friend’s boyfriend for coffee without telling her. All improper things are wrong in someone's eyes.

Definitions of improper
1

adj not suitable or right or appropriate

“slightly improper to dine alone with a married man”
improper medication”
improper attire for the golf course”
Synonyms:
inappropriate
not suitable for a particular occasion etc
indecent
offensive to good taste especially in sexual matters
indecorous, indelicate
lacking propriety and good taste in manners and conduct
unfit
below the required standards for a purpose
indecent, indecorous, unbecoming, uncomely, unseemly, untoward
not in keeping with accepted standards of what is right or proper in polite society
out-of-the-way
improper or even offensive
incorrect, wrong
not in accord with established usage or procedure
wrong
contrary to conscience or morality or law
Antonyms:
proper
marked by suitability or rightness or appropriateness
appropriate
suitable for a particular person or place or condition etc
correct, right
free from error; especially conforming to fact or truth
decent
conforming to conventions of sexual behavior
decorous
characterized by propriety and dignity and good taste in manners and conduct
becoming, comely, comme il faut, decent, decorous, seemly
according with custom or propriety
correct, right
socially right or correct
correct, right
in accord with accepted standards of usage or procedure
fitting
in harmony with the spirit of particular persons or occasion
halal
proper or legitimate
kosher
proper or legitimate
priggish, prim, prissy, prudish, puritanical, square-toed, straight-laced, straightlaced, strait-laced, straitlaced, tight-laced, victorian
exaggeratedly proper
right
in conformance with justice or law or morality
show more antonyms...

adj not appropriate for a purpose or occasion

Synonyms:
wrong
inappropriate
not suitable for a particular occasion etc

adj not conforming to legality, moral law, or social convention

improper banking practices”
Synonyms:
unconventional, unlawful
irregular
contrary to rule or accepted order or general practice

Sign up, it's free!

Whether you're a student, an educator, or a lifelong learner, Vocabulary.com can put you on the path to systematic vocabulary improvement.