[a. Fr. frettage, f. fretter to ring, f. frette FRET sb.5] a. The process of shrinking on rings of metal about the breech of a gun to give additional strength. b. The collection of rings thus employed.

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1882.  Rep. Chief of Ordnance, 244 (Cent. Dict.). The gun, one it has been tubed, ordinarily receives an exterior frettage.

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