Whitmonday[hwit′mun′dā, wit′-; -dē]
Whitmonday 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.
the Monday immediately following Whitsunday
Origin: after Whitsunday
Whitmonday definition by American Heritage Dictionary
The day after Whitsunday.