A mind of no calibre: of no capacity. A mind of great calibre: of large capacity. Calibre is the bore of a gun, and, figuratively, the bore or compass of one’s intelligence.
“The enemy had generally new arms … of uniform caliber.”—Grant: Memoirs, vol. i. chap. xxxix. p. 572.
“Wemeasure men’s calibre by the broadest circle of achievements.”—Chapin: Lessons of Faith, p. 16.
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