adjective
1.
unsuited to the circumstances or the occasion
wore quite improper dress for such a formal reception
Synonyms: ill-timed, inadmissible, inappropriate, inapt, inept, intempestive, malapropos, unapt, unbecoming, unbefitting, uncomely, undue, unfitting, unseasonable, unseemly, unsuitable, untimely
Related Word: infelicitous, unhappy; inapplicable, inapposite; fresh, impertinent, sassy; crude, gauche, tactless
Idioms: out of place, out of season
Contrasted words: apposite, appropriate, apropos, apt, becoming, befitting, felicitous, fitting, germane, happy, opportune, pat, pertinent, seasonable, suitable, timely, well-timed
Antonyms: proper
2.
Synonyms: indecorous , indecent, indelicate, malodorous, rough, unbecoming, undecorous, ungodly, unseemly, untoward
Related Word: informal, unceremonious, unconventional
Contrasted words: correct, right
Antonyms: proper