Pronunciation: (im-prop'ur), [key]
1. not proper; not strictly belonging, applicable, correct, etc.; erroneous: He drew improper conclusions from the scant evidence.
2. not in accordance with propriety of behavior, manners, etc.: improper conduct at a funeral.
3. unsuitable or inappropriate, as for the purpose or occasion: improper attire for a formal dance.
4. abnormal or irregular: improper functioning of the speech mechanism.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.