goose neck - The hoop which attaches the boom to the mast.

gudgeon - The assembly of bracket attached to the transom of the boat on which the rudder is mounted.

gybe - When running, to change direction during which the boom changes sides.

halyard - The rope used to pull up the sail.

head - The top of the sail.

head to wind - aimed directly into the wind

heel - when the boat tips to the side

helm - The steering mechanism

hike out - To lean out to windward when the boat heels

hiking strap - A strap in the cockpit which you put your feet under when you hike

in irons - When the boat goes backwards because the wind is coming from straight ahead.  If you get in irons, push the tiller to one side of the boat and the boom to the other until the boat is sidewise to the wind.  Then sheet in and straighten the tiller.

Interested Party - A person who may gain or lose as a result of protest committee’s decision, or who has a close personal interest in the decision. (ISAF Rules)

jib - The sail in front of the mast.

keel - A fixed foil extending down from the bottom of the boat to prevent sideslipping.

Keep Clear - One boat keeps clear of another if the other can sail her course with no need to take avoiding action and, when the boats are overlapped on the same tack, if the leeward boat can change course in both directions without immediately making contact with the windward boat. (ISAAF Rules)