decency (n.)

1560s, "appropriateness, state or quality of being fit or suitable," from Latin decentia "comeliness, decency," from decentem "becoming, fitting," present participle of decere "to be fitting or suitable," from PIE *deke-, from root *dek- "to take, accept." Meaning "modesty, freedom from ribaldry or obscenity" (i.e. "appropriateness to standards of society") is from 1630s.