 200px|thumb|7: skeg a skeg, (skegg or skag) is a sternward extension of the keel of boats and ships which have a rudder mounted on the centre line. the term also applies to the lowest point on an outboard motor or the outdrive of an inboard/outboard."a small fin fitted aft of the keel to protect the rudder and propeller, and improve steering and tracking." "skeg, or skegg. a projecting stump formerly left on the keel, abaft the stern-post. the after-end of the keel. the composition piece supporting the heel of an equipoise rudder."  at internet archive in more recent years, the name has been used for a fin on a surfboard which improves directional stability and to a moveable fin on a kayak which adjusts the boat's centre of lateral resistance (it moves the center of resistance relative to the center of effort). the term is also often used for the fin on water skis in the u.s. and for the tail bumpers of aircraft i
Nautical_terms Naval_architecture Sailboat_components Sailing_rigs_and_rigging Sailing_ship_components Shipbuilding Surfing_equipment