Improper Im*prop"er, a. [F. impropre, L. improprius; pref. im- not + proprius proper. See {Proper}.] 1. Not proper; not suitable; not fitted to the circumstances, design, or end; unfit; not becoming; incongruous; inappropriate; indecent; as, an improper medicine; improper thought, behavior, language, dress. [1913 Webster]

Follow'd his enemy king, and did him service, Improper for a slave. --Shak. [1913 Webster]

And to their proper operation still, Ascribe all Good; to their improper, Ill. --Pope. [1913 Webster]

2. Not peculiar or appropriate to individuals; general; common. [Obs.] [1913 Webster]

Not to be adorned with any art but such improper ones as nature is said to bestow, as singing and poetry. --J. Fletcher. [1913 Webster]

3. Not according to facts; inaccurate; erroneous. [1913 Webster]

{Improper diphthong}. See under {Diphthong}.

{Improper feud}, an original feud, not earned by military service. --Mozley & W.

{Improper fraction}. See under {Fraction}. [1913 Webster]

The Collaborative International Dictionary of English. 2000.