A printers’ abbreviation of capitals, capital letters.

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1850.  Thackeray, Pendennis, xxxii. We’ll have that in large Caps., Bungay, my boy.

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1905.  Niles Daily Star, 17 Jan., 4/2. The eyes of the people are trained to read lower case letters, and a line set in all caps is usually somewhat indistinct.

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