lad – a young boy.
landlubber (or just lubber) - a person unfamiliar with sailing or the sea.
lanyard (or laniard) – a rope affixed to something to use as a handle; also a rope used in one type of cannon-firing mechanism.
lass – a young girl.
lateen sail – a large triangular fore-and-aft sail.
league – a measurement of distance, equal to something around 3 miles.
lee side – the side of the ship away from the source of the wind
leeward – the opposite of the direction from which the wind is coming
letters of marque – an official license provided by a government empowering a private vessel to attack ships of other nations on the commissioning nation’s behalf. It was a small step for a ship to go from acting lawfully under Letters of Marquee to full-fledged piracy.
lily-livered – cowardly
loaded to the gunwall – The term literally indicates that a ship that was carrying all the cargo it possible could, but it was often used as a euphemism for someone being drunk.
log – a book in which information about the activities of the ship were recorded.
long boat - a boat carried aboard ship, typically with room for eight to ten oarsman.
long clothes – fancy clothes, not suitable for wearing during ones normal duties at sea.
loot – treasure
lugger – a ship characterized by having lugsails
lugsail – a sail that is similar to a square-rigged sail, the difference being that where a square-rigged sail is lifted directly along the center, a lugsail has its halyard offset to one side.
