leeway

noun

1. extra time, space, materials, or the like, within which to operate; margin: With ten minutes’ leeway we can catch the train.
2. a degree of freedom of action or thought: His instructions gave us plenty of leeway.
3. Also called sag. Nautical. the amount or angle of the drift of a ship to leeward from its heading.
4. Aeronautics. the amount a plane is blown off its normal course by cross winds.

noun

1. room for free movement within limits, as in action or expenditure
2. sideways drift of a boat or aircraft

n.1660s, sideways drift of a ship caused by wind, from lee + way. Figurative meaning “extra space” is by 1835.