n. An international distress signal used by shipping and aircraft
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. an internationally recognized distress signal via radiotelephone (from the French m'aider)
Word Usage
"At about 1648 hours, the U.S. Air Force airborne command post, Hillsborough, received a mayday from the two OV1 aircraft, and dispatched two FACs in the area for an immediate search for the two downed air crews."