noun.
The drift of a ship or aircraft to leeward of the course being steered.
noun.
A margin of freedom or variation, as of activity, time, or expenditure; latitude. synonym: room.
The Century Dictionary and Cyclopedia
noun.
The lateral movement of a ship to the leeward of her course, or the angle formed between the line of the ship's keel and the line which she actually describes through the water; the deviation from her true course which a vessel makes by drifting to leeward.
noun.
Hence Loss of progress in general; a falling behind; retrogression: as, to be making leeway financially.
the GNU version of the Collaborative International Dictionary of English
noun.
The lateral movement of a ship to the leeward of her course; drift.