from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A gentle slope; an incline.
  • noun A slope extending down from a fortification.
  • noun A neutral area separating conflicting forces.

from The Century Dictionary.

  • noun A gentle slope or sloping bank.
  • noun An easy slope, like that of the shingle piled on the shore by the action of the tides and waves, less steep than a talus.

from the GNU version of the Collaborative International Dictionary of English.

  • noun A gentle slope, or a smooth, gently sloping bank; especially (Fort.), that slope of earth which inclines from the covered way toward the exterior ground or country (see Illust. of ravelin).

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun military A gentle incline in front of a fortification.
  • noun military The angled armour plate on the front of a tank; glacis plate.
  • noun postal service A device for sorting mail which slides parcels across a sloped surface.


from The American Heritage® Dictionary of the English Language, 4th Edition

[French, from Old French, from glacer, to slide, from glace, ice, from Vulgar Latin *glacia, from Latin glaciēs; see gel- in Indo-European roots.]


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  • Thus the ground beyond the ditch, that is, the glacis, covers the walls from the shot of a besieger, and renders it extremely difficult to reach them.

    The Young Buglers 1867

  • The glacis is the smooth ground outside the ditch.

    The Young Buglers 1867

  • The purpose of the glacis, which is an inclined plane, is to expose an attacking party to the fire of the guns, which are so placed as to sweep it from the crest of the counterscarp to the edge of the beach.

    Fort Moultrie 1861

  • At the base is a kind of glacis, which runs up at an angle of forty-five from the plain to within fifty, and, in some places, within twenty feet of the foot of the wall.

    Rambles and Recollections of an Indian Official William Sleeman 1822

  • The Germans labored up the glacis slowly at the most exposed places; now crawling on their bellies, now creeping on hands and knees, but, in the main, moving with erect and steady bearing.

    She Makes Her Mouth Small & Round & Other Stories 2010

  • This crusts over the whole glacis of the eastern and northern parts of the piedmont giving very poor soils, usually skeletal lithosols if present at all.

    Mount Nimba Strict Nature Reserve, Guinea and Côte d'Ivoire 2008

  • It rises abruptly 1,000 m above an almost flat surrounding glacis.

    Mount Nimba Strict Nature Reserve, Guinea and Côte d'Ivoire 2008

  • Again there was no moat, just a glacis, so that they had to mount a kind of stone hill leading up to the wall.

    Labor Policy John Dermot Woods 2010

  • The landscape is characterized by volcanic piles with precipitous slopes, and deeply incised valleys (glacis slopes).

    Morne Trois Pitons, Dominica 2009

  • The inner walls of the Crac are ringed by a smooth slope called a glacis.

    A Medieval Castle in the Middle East Christian C. Sahner 2009


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  • Citation on counterscarp.

    July 30, 2008

  • "The Dwelling seemed to be a sort of town of rounded buildings more like lime-kilns than anything else, with arched doors leading to dark insides. They were all built of tiny stones, such as lay on the beach. Beyond the huts or houses towered the castle, a vast rough structure with towers and arches and buttresses and bastions and glacis and bridges and a great moat all around it."

    The Magic City by E. Nesbit, p 119 of the SeaStar Books paperback

    October 31, 2010

  • I found at least five different suggested pronunciations for glacis; also, some dictionaries treat it as a word of chiefly military application and only secondarily a term of geology while others reverse this balance. It is an oddly promiscuous word.

    November 17, 2014

  • For some there’s joy in steepest places;

    They burn to climb high alpine faces.

    But a diligent student

    Of what’s safe and prudent

    Will opt for a stroll on the glacis.

    November 17, 2014

  • Thank you for you precis of glacis.

    November 17, 2014

  • Wise bilby need not write it twice,

    Let’s lend an ear to his advice.

    We can use précis

    And rhyme it with glacis

    But there are some who say “glacis.”

    November 17, 2014

  • I love this glacis to piecis.

    November 17, 2014

  • And then there’s the word as spoke in Taz-ese,

    Where they improvise with loose jazz ease.

    In Van Diemen’s land

    (I have it first hand)

    They pronounce the word “glacis.”

    November 18, 2014

  • There once was a man from Caracas
    Who tried hard to rhyme the word glacis
    But try as he might
    His attempts were pure shite
    And gringo linguists thought he was crackers

    November 18, 2014

  • a weekend in glacis is bad for your homeostasis

    November 19, 2014