'Improper' definitions:

Definition of 'improper'

(from WordNet)
adjective
Not suitable or right or appropriate; "slightly improper to dine alone with a married man"; "improper medication"; "improper attire for the golf course" [ant: proper]
adjective
Not conforming to legality, moral law, or social convention; "an unconventional marriage"; "improper banking practices" [syn: improper, unconventional, unlawful]
adjective
Not appropriate for a purpose or occasion; "said all the wrong things" [syn: improper, wrong]

Definition of 'Improper'

From: GCIDE
  • Improper \Im*prop"er\, v. t. To appropriate; to limit. [Obs.] [1913 Webster]
  • He would in like manner improper and inclose the sunbeams to comfort the rich and not the poor. --Jewel. [1913 Webster]

Definition of 'Improper'

From: GCIDE
  • 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]

Synonyms of 'improper'

From: Moby Thesaurus