- The definition of a dinner jacket is a formal jacket or a tuxedo jacket.
An example of a dinner jacket is what a man might wear to a formal affair such as a dinner dance or his wedding.
A young man in a dinner jacket.
dinner jacket definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
a tuxedo jacket
dinner jacket definition by American Heritage Dictionary