• Webster's Revised Unabridged Dictionary
    • n Orillon (Fort) A semicircular projection made at the shoulder of a bastion for the purpose of covering the retired flank, -- found in old fortresses.
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Chambers's Twentieth Century Dictionary
    • n Orillon o-ril′lon a semicircular projection at the shoulder of a bastion intended to cover the guns and defenders on the flank.
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Webster's Revised Unabridged Dictionary
F., lit., a little ear, from oreille, an ear, fr. L. oricula, auricula, dim. of auris, an ear. See Ear
Chambers's Twentieth Century Dictionary
Fr.,—oreille, an ear—L. auricula, dim. of auris, ear.


In literature:

Now, Harlequins are very popular in Rue de l'Orillon.
"Monsieur Cherami" by Charles Paul de Kock
It may be observed that he sometimes uses the straight flank, and sometimes the curved flank with orillon.
"Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 6" by Various