If a ship is in grave and imminent danger what distress call does it make?

If a ship is in grave and imminent danger, it makes a distress call using the term "Mayday" repeated three times, followed by the vessel's name, position, and nature of the distress. This call is typically made on VHF channel 16 or via other communication methods. The Mayday call alerts nearby vessels and maritime authorities to provide immediate assistance.