Idioms and Phrases with not done
Socially unacceptable, improper, as in Bringing along two friends without asking, that's not done. [First half of 1900s]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.