A jibe or gybe is a sailing maneuver where a sailing vessel turns its stern through the wind, such that the wind direction changes from one side of the boat to the other. For square-rigged ships, this is called wearing ship and involves bringing the ship before the wind with braces carefully controlling the sails.

In this maneuver the mainsail will cross the center of the boat while the jib is pulled to the other side of the boat. If the spinnaker is up, the pole will have to be manually moved from one corner of the sail to the other. In a dinghy it is sometimes necessary to raise the centerboard to prevent the boat from capsizing during this somewhat violent maneuver.

The other way to change the side of the boat that faces the wind tack is turning the bow of the boat through the direction of the wind. This operation is known as tacking or coming about.

Spelling

While jibe and gybe are both acceptable spellings of the term, gybe is the more common spelling in British English, while jibe in American English.

Use

Jibing is a less common technique than tacking, since a sailboat can sail straight downwind, whereas it cannot sail directly into the wind and has to tack or sail zig-zagged at alternating angles into the wind. However, many sailboats are significantly faster sailing on a broad reach than running (sailing straight downwind), so the increased speed of a zig-zag course of alternating broad reaches can make up for the extra distance it takes over a straight downwind course. The sailboat will execute a jibe maneuver when it changes course as it zig-zags downwind. Jibing is also used commonly in races, which often use a triangular course marked with buoys; the most direct way of rounding a buoy may be to jibe. A jibe can generally be completed more quickly than a tack because the boat never turns into the wind, and thus a jibing boat's sails are always powered where a tacking boat's sails are unpowered as the bow crosses into the direction of the wind.

Because of the inherent dangers in jibing (uncontrolled, the boom can travel almost 180º with great speed and lethal force), communication with the crew is important. The Helm should use three commands when jibing: ‘Prepare to Jibe', ‘Bearing Away' and ‘Jibe Ho'.

Over time, too many boats have forgotten to say ‘Bearing Away' and use ‘Jibe Ho' at the start of the evolution. Then when the boom comes over they don't know what to say and usually someone yells “watch it, watch it, watch it!” This is wrong.

The correct way is the Helm says “Prepare to Jibe” to get everyone in position and ready for the jibe, and then says “Bearing Away” (similar to saying “Helms a Lee” during a tack) at the start of the evolution when the Helm actually applies rudder action to change course. Next, when the Helm wants to move the boom to the other side, the Helm says “Jibe Ho.” ‘Jibe Ho' is the command (warning) to use when and only when the boom is coming across.