• WordNet 3.6
    • n declivity a downward slope or bend
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Webster's Revised Unabridged Dictionary
    • Declivity A descending surface; a sloping place. "Commodious declivities and channels for the passage of the waters."
    • Declivity Deviation from a horizontal line; gradual descent of surface; inclination downward; slope; -- opposed to acclivity, or ascent; the same slope, considered as descending, being a declivity, which, considered as ascending, is an acclivity.
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Century Dictionary and Cyclopedia
    • n declivity A downward slope. Specifically— The portion of a hill or range of mountains lying on one side or the other of the crest or axis.
    • n declivity In entomology, a part gently sloping away from the general plane of a surface.
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Chambers's Twentieth Century Dictionary
    • n Declivity de-kliv′i-ti a place that declines, or slopes downward, opposite of acclivity: inclination downward: a gradual descent
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Webster's Revised Unabridged Dictionary
L. declivitas, fr. declivis, sloping, downhill; de, + clivus, a slope, a hill; akin to clinare, to incline: cf. F. déclivité,. See Decline
Chambers's Twentieth Century Dictionary
Fr.,—L. declivitasde, downward, clivus, sloping, akin to clināre.


In literature:

Rough-locking is a very safe method of passing heavy artillery down abrupt declivities.
"The Prairie Traveler" by Randolph Marcy
Arrived at the bottom of the declivity, the captain abruptly paused; and Jim Chowder and Jan, who were close behind, came up with him.
"The Island Treasure" by John Conroy Hutcheson
The declivity of the hill enabled the scouts to run with swiftness; and they were among the trees almost as soon as we.
"The War Trail" by Mayne Reid
This good ground was for the most part on the declivities of the hills, and so on below.
"Journal of Jasper Danckaerts, 1679-1680" by Jasper Danckaerts
Shortly, however, after descending a declivity, we turned into a lane, at the entrance of which was a gate.
"Lavengro The Scholar, the Gypsy, the Priest" by George Borrow
The hills, though of great declivity, have a sward to their tops.
"Handbook to the new Gold-fields" by R. M. Ballantyne
They trooped along in files and columns, bulls, cows, and calves, on the green faces of the declivities in front.
"Journeys Through Bookland, Vol. 7" by Charles H. Sylvester
Water runs faster down a steep hill than down a gentle declivity.
"Farm drainage" by Henry Flagg French
The country in this region is hilly, with here and there steep declivities and peaks of considerable elevation.
"The Story of the Great War, Volume V (of 12)"
It was built on the declivities of the mountains, which here crowd close upon the sea.
"Rollo in Naples" by Jacob Abbott
On and up we went, ascending a gentle declivity until we came to a brook said to be two miles from the boat landing.
"The Continental Monthly, Vol. 6, No. 6, December 1864" by Various
The declivity marks the end of the precipitous gorge of the Niagara.
"Fragments of science, V. 1-2" by John Tyndall
To this he directed his steps, and ascended the steep declivity up to the top of the hill.
"The Martyr of the Catacombs" by Anonymous
This full-page cartoon represented a young dude, seated on a mule, riding down a steep declivity.
"Bidwell's Travels, from Wall Street to London Prison" by Austin Biron Bidwell
Shots up or down a declivity usually miss.
"A Treatise on the Tactical Use of the Three Arms: Infantry, Artillery, and Cavalry" by Francis J. Lippitt
What hand had guided him down the declivities of the Palatine?
""Unto Caesar"" by Baroness Emmuska Orczy
They frequently serve better than either asses or mules, as they can pass up and down declivities where neither ass nor mule can travel.
"The Forest Exiles" by Mayne Reid
I quickly scrambled down the declivity, and was not long in reaching the point from which Ruth fell.
"Roger Trewinion" by Joseph Hocking
Here we made out a cave, above which was a grassy declivity sloping upwards towards the summit.
"A Yacht Voyage Round England" by W.H.G. Kingston
"A Son of Hagar" by Sir Hall Caine

In poetry:

The mountain, with the snow bank crowned;
The gorge, abysmal and profound;
Impress with aspect grand:
With unfeigned reverence I see
In canon and declivity
The All-Wise Hand.
"There Is An Air Of Majesty." by Alfred Castner King
A wilderness of weird, fantastic shapes,
Of precipice and stern declivity;
Of dizzy heights, and towering minarets;
Colossal columns and basaltic spires
Which pointing heavenward, appeared to wave
In benediction o'er the depths beneath.
"Grandeur." by Alfred Castner King