From , from , from in- + proprius ("proper"), equivalent to .

• (RP) IPA: /ɪmˈpɹɒp.ə/
• (Australia) IPA: /ɪmˈpɹɔp.ə/
• (America) IPA: /ɪmˈpɹɑ.pɚ/

improper

1. unsuitable to needs or circumstances; inappropriate; inapt
2. Not in keeping with conventional mores or good manners; indecent or immodest

   improper conduct

3. Not according to facts; inaccurate or erroneous
4. Not consistent with established facts; incorrect
5. Not properly named; See, for example, improper fraction
6. (obsolete) Not specific or appropriate to individuals; general; common.
7. (mathematics) Of a complex random variable, correlated with its conjugate

• unproper (obsolete or rare)

• French: impropre, inapproprié, inadapté
• German: unpassend
• Portuguese: impróprio
• Russian: неуме́стный

• French: impropre, inconvenant, grossier
• German: unhöflich
• Portuguese: impróprio, indecente, indecoroso
• Russian: непристо́йный
• Spanish: improprio

• Portuguese: impróprio, incorreto
• Russian: непра́вильный

• Portuguese: impróprio, incorreto
• Russian: непра́вильный

• French: impropre
• Portuguese: impróprio

improper (impropers, present participle impropering; simple past and past participle impropered)

1. (obsolete, transitive) To appropriate; to limit.
   • 1565, John Jewel, letter to Thomas Harding:

     He would in like manner improper and inclose the sunbeams to comfort the rich and not the poor.

2. (obsolete) To behave improperly