[ad. L. quadruplicāt-us, pa. pple. of quadruplicāre to quadruple, f. quadruplex: see prec.]
A. adj. 1. Fourfold; four times repeated. Quadruplicate proportion, ratio, the proportion or ratio of fourth powers in relation to that of the radical quantities.
1657. Hobbes, Absurd Geom., Wks. 1845, VII. 378. An infinite row of Arithmetically proportionals, in proportion quadruplicate.
1794. G. Adams, Nat. & Exp. Philos., III. xxxi. 269. The efforts tending to destroy the adhesion of beams from their gravity only, increase in the quadruplicate ratio of their lengths.
1816. Playfair, Nat. Phil., II. 169. The same [probability] is increased in a quadruplicate ratio, from considering the phenomena of all these four superior planets.
2. Forming four exactly corresponding copies.
1807. Pike, Sources Mississ., III. App. (1810), 72. I have directed the formula for you to sign of four corresponding quadruplicate receipts.
B. sb. 1. In quadruplicate: In four exactly corresponding copies or transcripts.
1790. W. Hastings, Lett. to Boswell, 2 Dec. in B.’s Johnson, an. 1781. Of these [letters], one which was written in quadruplicate … has already been made publick.
1900. Rules (25 Oct.) under Money-Lenders Act, vi. The order shall be signed in quadruplicate by the permanent Secretary.
fig. 1886. Kipling, Departm. Ditties, etc. (1899), 47. Four times Cupid’s debtor I—Bankrupt in quadruplicate.
2. pl. Four things exactly alike; esp. four exactly corresponding copies of a document.
1883. Sir C. S. C. Bowen, in Law Rep. 11 Q. Bench Div. 342. The … conveniences which merchants … believed to be afforded by the system of triplicates or quadruplicates.
