Origin: 1350–1400; Middle English preparacion < Latin praeparātiōn- (stem of praeparātiō), a preparing, equivalent to praeparāt(us) (past participle of praeparāre to prepare) + -iōn--ion
1390, "act of preparing," from L. præparationem (nom. præparatio) "a making ready," from præparatus, pp. of præparare "prepare," from præ- "before" + parare "make ready" (see pare). Meaning "a substance especially prepared" is from 1646. Verb prepare
is attested from 1466, from M.Fr. preparer, from L. præparare; slang shortening prep is from 1927. Preparatory is first recorded 1413, from L.L. præparatorius, from L. præparatus. Applied from 1822 to junior schools in which pupils are "prepared" for a higher school.