1. The stem or forward end of a boat. (please see Bow where this concept is covered more fully.) Also the upper end of a spar, as in Masthead. (Though see Truck, which may be useful to you.) The Head of a sail is the top corner of a trian¬gular one, or the whole top edge of a four-sided one. (And see Tack and Clew.) The upper extremity of the Rudder stock is the head.
2. Of a pier or jetty, the seaward end. The other end is the Root.