pray (v.)youdaoicibaDictYouDict[pray 词源字典]
early 13c., "ask earnestly, beg," also (c. 1300) "pray to a god or saint," from Old French preier "to pray" (c.900, Modern French prier), from Vulgar Latin *precare (also source of Italian pregare), from Latin precari "ask earnestly, beg, entreat," from *prex (plural preces, genitive precis) "prayer, request, entreaty," from PIE root *prek- "to ask, request, entreat" (cognates: Sanskrit prasna-, Avestan frashna- "question;" Old Church Slavonic prositi, Lithuanian prasyti "to ask, beg;" Old High German frahen, German fragen, Old English fricgan "to ask" a question).

Parenthetical expression I pray you, "please, if you will," attested from 1510s, contracted to pray 16c. Related: Prayed; praying. Praying mantis attested from 1809. The "Gardener's Monthly" of July 1861 lists other names for it as camel cricket, soothsayer, and rear horse.[pray etymology, pray origin, 英语词源]
prayer (n.)youdaoicibaDictYouDict
c. 1300, from Old French prier "prayer, petition, request" (12c., Modern French prière), from Medieval Latin precaria "petition, prayer," noun use of Latin adjective precaria, fem. of precarius "obtained by prayer, given as a favor," from precari "to ask, beg, pray" (see pray). Related: Prayers.

Prayer-book attested from 1590s; prayer-meeting from 1780. To not have a prayer "have no chance" is from 1941.
prayerful (adj.)youdaoicibaDictYouDict
1620s, from prayer + -ful. Related: Prayerfully; prayerfulness.
pre-youdaoicibaDictYouDict
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- (cognates: 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 see prae-. Sometimes in Middle English muddled with words in pro- or per-.
pre-arrange (v.)youdaoicibaDictYouDict
also prearrange, 1792 (implied in pre-arranged), from pre- + arrange. Related: Pre-arranging.
pre-arrangement (n.)youdaoicibaDictYouDict
also prearrangement, 1775, from pre- + arrangement.
pre-atomic (adj.)youdaoicibaDictYouDict
"before the atomic age," 1914, in "World Set Free" -- H.G. Wells anticipating the word the future would use to look back at a time defined by events that hadn't yet happened in his day; from pre- + atomic.
pre-date (v.)youdaoicibaDictYouDict
also predate, 1859, "to antedate, to assign an earlier date to," from pre- + date (n.1) "point in time." As "to exist before," from 1857. Related: Pre-dated; pre-dating.
pre-dawn (adj.)youdaoicibaDictYouDict
1940, from pre- + dawn (n.).
pre-eclampsia (n.)youdaoicibaDictYouDict
also preeclampsia, 1903, from pre- + eclampsia. Related: Pre-eclamptic (1896).
pre-elect (v.)youdaoicibaDictYouDict
1560s, from pre- + elect (v.). Related: Pre-elected; pre-electing.
pre-election (n.)youdaoicibaDictYouDict
1580s, from pre- + election.
pre-electric (adj.)youdaoicibaDictYouDict
1894, from pre- + electric.
pre-eminence (n.)youdaoicibaDictYouDict
also pre-eminence, c. 1200, from Late Latin praeeminentia "distinction, superiority," from Latin praeeminentem (nominative praeeminens), present participle of praeeminere "transcend, excel," literally "project forward, rise above," from prae "before" (see pre-) + eminere "stand out, project" (see eminent).
pre-eminent (adj.)youdaoicibaDictYouDict
also preeminent, mid-15c., from Medieval Latin preeminentem, from Latin praeeminentem (nominative praeeminens), present participle of praeeminare "to transcend, excel," literally "to project forward, rise above" (see pre-eminence). Related: Pre-eminently; preeminently.
pre-empt (v.)youdaoicibaDictYouDict
also preempt, 1830, "secure by pre-emtion," back-formation from pre-emption, originally American English. In the broascasting sense, it is attested from 1965, American English, a euphemism for "cancel." Related: pre-empted; preempted.
pre-emption (n.)youdaoicibaDictYouDict
also preemption, c. 1600, literally "the right of purchasing before others," from pre- "before" + emption.
pre-emptive (adj.)youdaoicibaDictYouDict
also preemptive, 1806, "pertaining to preemption;" from pre-emption + -ive. Specifically of an attack on an enemy who is plotting his own attack, 1958, a term from the Cold War. Related: Pre-emptively; preemptively.
pre-emptory (adj.)youdaoicibaDictYouDict
also preemptory, 1822, "relating to pre-emption," from pre-emption + -ory.
pre-engage (v.)youdaoicibaDictYouDict
"bind in advance by promise," 1640s, from pre- + engage (v.). Related: Pre-engaged; pre-engaging.