A boomkin projecting from the bow of HMS Surprise (in center of image)

A boomkin, bumkin, or bumpkin is a short spar that may project either fore or aft on a sailing vessel, depending on its function. Traditionally, it was a strong, usually wooden spar extending forward over the bow of a Western sailing ship holding a block through which the tack of the foresail was passed; on some modern sailing yachts with long main booms it is a short spar extending aft from the stern anchoring a central backstay.[1]

Historically, boomkins were employed in pairs, one on either side of the vessel, often canted downwards over the main head-rail. Originally butted at their inboard ends against a knighthead, bolting prevailed since the end of the 18th century.

They are not to be confused with catheads, heavy wooden beams on either side of a traditional vessel's bow angled forward at roughly 45 degrees which support the ship's anchors when being raised or lowered.


Traditional boomkins found on English sailing vessels gradually evolved from 1710 until around 1850.[1]

Photo of the mizzen sail boomkin on 1980 Drascombe Lugger Onkahye sliding gunter rig yawl


  1. ^ a b Goodwin, Peter G. (1987). The construction and fitting of the English man of war, 1650-1850. London: Conway. pp. 223–225. ISBN 0-87021-016-5.