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.