Lazy Sheet

A lazy sheet is a line that is rigged to be used as a sheet, but is currently not doing anything.

For example, two lines might be tied to the clew of a jib sail to be used as sheets. When the boat is on starboard tack, the port side jib sheet will be under tension, and the starboard side line should be slack. So the starboard line is referred to as the lazy sheet.

Other lines, such as guys and preventers, can be be referred to as "lazy" if they are currently not being used because of the tack of the boat, or similar reason.