C16: from French apostille, from Old French apostiller to make marginal notes, from Medieval Latin postilla, probably from Latin post illa (verba) after those (words)
apostil in American English
(əˈpɑstɪl) or aˈpostille (əˈpɑstɪl)
noun
a note, esp. one in the margin
Word origin
Fr apostille < à, to + postille, marginal note < ML postilla < L post illa, lit., after these