noun the roundest part of a ship's bow.
2. luff ·noun the side of a ship toward the wind.
3. luff ·noun the act of sailing a ship close to the wind.
4. luff ·noun the forward or weather leech of a sail, especially of the jib, spanker, and other fore-and-aft sails.
5. luff ·vi to turn the head of a vessel toward the wind; to sail nearer the wind; to turn the tiller so as to make the vessel sail nearer the wind.