The United States flag at half-mast.
half-mast 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 position of a flag lowered about halfway down a mast, staff, etc., esp. as a sign of mourning
to fly (a flag) at half-mast
half-mast definition by American Heritage Dictionary
The position about halfway up a mast or pole at which a flag is flown as a symbol of mourning for the dead or as a signal of distress. Also called half-staff.transitive verb half-mast·ed, half-mast·ing, half-masts
To place (a flag) halfway up a mast or pole.