Adjective improper has 3 senses
- improper - not suitable or right or appropriate; "slightly improper to dine alone with a married man"; "improper medication"
Antonyms: proper, becoming, comely, comme il faut, decent, decorous, seemly, correct, right, fitting, halal, kosher, priggish, prim, prissy, prudish, puritanical, square-toed, straitlaced, strait-laced, straightlaced, straight-laced, tight-laced, victorian
- improper, unconventional, unlawful - not conforming to legality, moral law, or social convention; "an unconventional marriage"; "improper banking practices"
Antonym: regular (indirect, via irregular)
- unsuitable, improper, wrong - not appropriate for a purpose or occasion; "unsuitable attire for the office"; "said all the wrong things"
Antonym: appropriate (indirect, via inappropriate)
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