A boomkin, sometimes referred to as a bumkin or as a bumpkin, consists of an exceptionally strong and usually wooden spar that projects forwards and often (though not always) downwards over the main head-rail of a traditional western sailing ship, one on either side of the vessel (not to be confused with cathead). The heel of this spar is usually either butted against a knighthead or is bolted to it (bolting being more common from the end of the 18th century forwards).

Parts of a sail
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Sailing rig
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