Origin and history of preconceive

late 13c., conceiven, "take (seed) into the womb, become pregnant," from stem of Old French conceveir (Modern French concevoir), from Latin concipere (past participle conceptus) "to take in and hold; become pregnant" (source also of Spanish concebir, Portuguese concebre, Italian concepere), from con-, here perhaps an intensive prefix (see con-), + combining form of capere "to take" (from PIE root *kap- "to grasp").

Meaning "take into the mind, form a correct notion of" is from mid-14c., that of "form as a general notion in the mind" is from late 14c., figurative senses also found in the Old French and Latin words. Related: Conceived; conceiving.

Nearly all the senses found in Fr. and Eng. were already developed in L., where the primary notion was app. 'to take effectively, take to oneself, take in and hold'. [OED]

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-.