indecorous

/ɪnˈdɛˈkɔrəs/

Indecorous behavior isn't proper or socially acceptable. It would be indecorous to publish your sister's diary in the newspaper or to tell your extended family an offensive joke at Thanksgiving dinner.

Rude or off-color remarks are indecorous, and wearing a bikini to a formal dinner would also be indecorous. Indecorous things lack decorum, which is good manners or proper behavior. Indecorous, from the Latin decorus, "becoming or seemly," comes from the root word decus, "ornament," and is related to words like "decorate" and "decent."

Definitions of indecorous

1. adjective

   lacking propriety and good taste in manners and conduct
   “indecorous behavior”

   synonyms: indelicate

   indecent

   offensive to good taste especially in sexual matters

   improper

   not suitable or right or appropriate

   antonyms:

   decorous

   characterized by propriety and dignity and good taste in manners and conduct

   in good taste

   satisfying generally accepted social or esthetic standards

   sedate, staid

   characterized by dignity and propriety

   proper

   marked by suitability or rightness or appropriateness
2. adjective

   not in keeping with accepted standards of what is right or proper in polite society
   “indecorous behavior”

   synonyms: indecent, unbecoming, uncomely, unseemly, untoward

   improper

   not suitable or right or appropriate