What is a polywog, and what happens during the crossing-the-line ceremony?
Short answerA polywog is a sailor who has not yet completed the equator-crossing initiation; afterward the sailor is recognized as a shellback.
NotesA polywog has yet to pass the initiation associated chiefly with crossing the equator; a sailor who completes it becomes a shellback. Related ceremonies have existed for other geographical crossings. Crew members were expected to participate regardless of rank or specialty, while cruise passengers generally had a choice. Selecting Neptune and the rest of the ceremonial court could involve considerable good-natured competition within a crew. A captain undergoing initiation still took part, although the crew usually handled that ceremony more diplomatically.