preprocess v.

word-forming element meaning "before," from Old French pre- and Medieval Latin pre-, both from Latin prae (adverb and preposition) "before in time or place," from PIE *peri- (source also of Oscan prai, Umbrian pre, Sanskrit pare "thereupon," Greek parai "at," Gaulish are- "at, before," Lithuanian prie "at," Old Church Slavonic pri "at," Gothic faura, Old English fore "before"), extended form of root *per- (1) "forward," hence "beyond, in front of, before."

The Latin word was active in forming verbs. Also see prae-. Sometimes in Middle English muddled with words in pro- or per-.

early 14c., proces, "fact of being carried on" (as in in process), from Old French proces "a journey; continuation, development; legal trial" (13c.) and directly from Latin processus "a going forward, advance, progress," from past-participle stem of procedere "go forward" (see proceed).

Meaning "course or method of action, continuous action or series of actions or events" is from mid-14c.; sense of "continuous and regular series of actions meant to accomplish some result" (the main modern sense) is from 1620s. Meaning "a projection from the main body of something," especially a natural appendage, is from 1570s. Legal sense of "course of action of a suit at law, the whole of the proceedings in any action at law" is attested from early 14c.; hence due process "fair treatment" at law, considered as a right (mid-15c.).