indecorous, improper, unseemly, unbecoming, indelicate mean not conforming to what is accepted as right, fitting, or in good taste. indecorous suggests a violation of accepted standards of good manners.

Improper definition: not proper; not strictly belonging, applicable, correct, etc.; erroneous.. See examples of IMPROPER used in a sentence.

improper adjective (WRONG) unsuitable or not correct for a particular use or occasion: improper prescription of medicines

1. not proper; not strictly belonging, applicable, or correct: drew improper conclusions. 2. not in accordance with propriety or regulations: improper conduct. 3. abnormal; irregular. im•prop′er•ness, n.

Nov 30, 2025 · improper (comparative more improper, superlative most improper) Unsuitable to needs or circumstances; inappropriate; inapt. Not in keeping with conventional mores or good manners; …

If you describe someone's behaviour as improper, you mean that it is rude or shocking.

Definition of improper adjective in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

unsuitable or inappropriate, as for the purpose or occasion: improper attire for a formal dance. abnormal or irregular: improper functioning of the speech mechanism.

There are five meanings listed in OED's entry for the adjective improper, one of which is labelled obsolete. See ‘Meaning & use’ for definitions, usage, and quotation evidence.

How does the adjective improper differ from other similar words? Some common synonyms of improper are indecorous, indelicate, unbecoming, and unseemly.