A forebitter is a sea song usually sung by sailors while at rest, rather than to mark rhythm for a shipboard task. These songs were originally sung by sailors gathered around the forebitts, a sturdy structure near the bow of a ship. As recreational songs, forebitters were sung primarily during fair weather; on rougher passages, there was precious little time for anything but work and sleep. Unlike the working shanties, where the crew would need their hands for hauling the lines and so forth, many were accompanied by music on the fiddle, banjo or other insturments. Quite often, they were popular ballads from shore, and covered surprisingly sentimental themes. Though the sailors were rough, tough men, they did miss the same things anyone else would while they were at sea.
Examples of forebitters include:
Sources:
http://www.sover.net/~barrand/rgh/westernocean.html
http://www.tamu.edu/univrel/aggiedaily/news/stories/archive/111897-3.html
The Oxford Book of Sea Songs, edited by Roy Palmer