To shorten sail

(Naut.) to reduce the extent of sail, or take in a part.
(Naut.) to reduce sail by taking it in.

See also: Sail, Shorten

Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in classic literature ?
On the 11th of January, 1833, by carrying a press of sail, we fetched within a few miles of the great rugged mountain of York Minster (so called by Captain Cook, and the origin of the name of the elder Fuegian), when a violent squall compelled us to shorten sail and stand out to sea.
I could see that if I wanted to go a-visiting any distance from home, and the wind was ahead, I might have to wait days, maybe, for a change; and I could see, too, that these things could not be any use at all in a gale; if you tried to run before the wind, you would make a mess of it, for there isn't anyway to shorten sail - like reefing, you know - you have to take it ALL in - shut your feathers down flat to your sides.
The captain said we ought to shorten sail anyway, out of common prudence.
For the best of it was that Captain S- seemed constitutionally incapable of giving his officers a definite order to shorten sail; and so that extraordinarily vague row would go on till at last it dawned upon them both, in some particularly alarming gust, that it was time to do something.