knighthead

A musketoon-ball struck the Sophie's starboard knighthead and he heard a seaman rip out a string of furious obscenity.

Jack stood there by the starboard knighthead, willing the sloop on with all his might, and feeling that his right arm might not be too great a price for an effective bow-chaser.

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).