Word Origin & History
late 14c., "to mark (a book) with chapter numbers or marginal references," from O.Fr. coter, from M.L. quotare "distinguish by numbers, number chapters," from L. quotus "which, what number (in sequence)," from quot "how many," related to quis "who." The sense development is via "to give as a reference,
to cite as an authority" to "to copy out exact words" (1670s). The business sense of "to state the price of a commodity" (1866) revives the etymological meaning. The noun, in the sense of "quotation," is attested from 1885. Quotable is from 1821. Unquote first recorded 1935, in a letter by e e cummings.