topscriptn. [after postscriptn.1] something written at the top of a letter.ⓘApparently an isolated use.
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society > communication > correspondence > letter > [noun] > antescript
topscript1731
antescript1767
1731 B. GermainLet. 4 Nov. in J. Swift Wks. (1841) II. 663 So much for your topscript, not postscript;..I heartily thank you for remembering me so often.