luff / ləf/ chiefly Sailing • n. the edge of a fore-and-aft sail next to the mast or stay.• v. [tr.] 1. steer (a sailing vessel) nearer the wind to the point at which the sails just begin to flap: I came aft and luffed her for the open sea. ∎  obstruct (an opponent in yacht racing) by sailing closer to the wind.2. raise or lower (the jib of a crane or derrick).

luff †contrivance for altering a ship's course XIII (often in phr. wend or turn the luff); †weather side of a ship XIV; side of a sail next to the mast XVI; broadest part of a ship's bow XVII. — OF. lof, prob. of LG. or Du. orig.
Hence luff vb. bring nearer to the wind. XIV (love). perh. immed. — Du. loeven.