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prae-

  1. variant of pre-.

pre-

  1. a prefix occurring originally in loanwords from Latin, where it meant “before” (preclude; prevent); applied freely as a prefix, with the meanings “prior to,” “in advance of,” “early,” “beforehand,” “before,” “in front of,” and with other figurative meanings (preschool; prewar; prepay; preoral; prefrontal).
Also prae-.

Origin of pre-

< Latin prae-, prefixal use of prae (preposition and adv.); akin to first, fore-, prior1, pro1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for prae-

prae-

prefix
  1. an archaic variant of pre-

pre-

prefix
  1. before in time, rank, order, position, etcpredate; pre-eminent; premeditation; prefrontal; preschool

Word Origin for pre-

from Latin prae-, from prae before, beforehand, in front
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for prae-

word-forming element meaning "before," from Latin prae (adv.) "before," from PIE *prai-, *prei-, from root *per- (1) "forward, through" (see per; also see pre-). Reduced to pre- in Medieval Latin. According to OED the full form prae- in Modern English appears "usually only in words that are still regarded as Latin, ... or that are terms of classical antiquity ...."

pre-

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- (cf. Oscan prai, Umbrian pre, Sanskrit pare "thereupon," Greek parai "at," Gaulish are- "at, before," Lithuanian pre "at," Old Church Slavonic pri "at," Gothic faura, Old English fore "before"), extended form of root *per- (1) "beyond" (see per).

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

Online Etymology Dictionary, © 2010 Douglas Harper
prae- in Medicine

pre-

pref.
  1. Earlier; before; prior to:prenatal.
  2. Anterior; in front of:preaxial.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.