Online Etymology Dictionary

prole (n.): short for proletarian (n.), 1887 (G.B. Shaw); popularized by George Orwell's 1949 novel "Nineteen Eighty-Four." As an adjective from 1938. Related: Proly (adj.); prolier-than-thou.
prolegomenon (n.): 1650s, "learned preamble to a book," from Greek prolegomenon, noun use of neuter passive present participle of prolegein "to say beforehand," from pro- "before" (see pro-) + legein "to speak" (see lecture (n.)) + suffix -menos (as in alumnus). The same sense is in preface (n.). Related: Prolegomenary; prolegomenous.
prolepsis (n.): 1570s, "the taking of something anticipated as already done or existing," from Latin prolepsis, from Greek prolepsis "an anticipating," literally "a taking beforehand," from prolambanein "to take before," from pro- "before" (see pro-) + lambanein "to take" (see analemma). Related: Proleptic; proleptical; proleptically.
proles (n.): "offspring," 1670s, from Latin proles "offspring, progeny" (see prolific).
proletarian: 1650s (n.) "member of the lowest class;" 1660s (adj.) "of the lowest class of people;" with -ian + Latin proletarius "citizen of the lowest class" (as an adjective, "relating to offspring"), in ancient Rome, propertyless people, exempted from taxes and military service, who served the state only by having children; from proles "offspring, progeny" (see prolific).
proletarianism (n.): 1844, from proletarian + -ism.
proletariat (n.): also proletariate, "the lowest class," 1853, from French prolétariat, from Latin proletarius (see proletarian). In political economics, "indigent wage-earners," from 1856. Leninist phrase dictatorship of the proletariat attested from 1918.
prolicide (n.): "killing of one's child or children," 1824, introduced by Dr. John Gordon Smith in the 2nd edition of his "Principles of Forensic Medicine;" from Latin proles "offspring" (see prolific) + -cide.
It is hoped that this word will be considered entitled to reception, on the score of analogy. We have long had parricide, fratricide, and infanticide, all (if I may use the figure of speech,) of the same family; and recently the very appropriate term foeticide has been introduced into Forensic Medicine. In both these last crimes there is a peculiarity arising from the person accused being, in almost every instance, the parent .... In this relation to the beings destroyed, the general term of murderer, or murder of offspring seems to be the fair converse of parricide; and will suit well the purpose of the Medico-legal writer, who considers the two cases as parts of one subject, for the designation of which collectively a proper term was wanting. [Smith]
proliferate (v.): 1857 as a term in biology; see proliferation. General sense from 1961. Related: Proliferated; proliferating.
proliferation (n.): 1859, "formation or development of cells," from French prolifération, from prolifère "producing offspring," from Latin proles "offspring" (see prolific) + ferre "to bear, carry" (see infer). Meaning "enlargement, extension, increase" is from 1920; especially of nuclear weapons (1966).
proliferative (adj.): 1868, from proliferate + -ive.
prolific (adj.): 1640s, from French prolifique (16c.), from Medieval Latin prolificus, from Latin proles "offspring" + root of facere "to make" (see factitious). Latin proles is contracted from *pro-oles, from PIE *pro-al-, from *pro- "forth" (see pro-) + *al- "to grow, nourish" (see old). Related: Prolifical (c. 1600).
Prolific is in common use, but to make a satisfactory noun from it has passed the wit of man. [Fowler]
prolix (adj.): early 15c., from Old French prolixe (13c.) and directly from Latin prolixus "extended," literally "poured out," from pro- "forth" (see pro-) + base of liquere "to flow" (see liquid (adj.)).
prolixity (n.): late 14c., from Old French prolixité "verbosity" (13c.), from Latin prolixitatem (nominative prolixitas), from prolixus (see prolix).
prologue (n.): early 14c., from Old French prologue (12c.) and directly from Latin prologus, from Greek prologos "preface to a play, speaker of a prologue," literally "a speech beforehand," from pro- "before" (see pro-) + logos "discourse, speech," from legein "to speak" (see lecture (n.)).
prolong (v.): early 15c., back-formation from prolongation or else from Old French prolonguer, porloignier (13c.), from Late Latin prolongare "to prolong, extend," from Latin pro- "forth" (see pro-) + longus "long" (adj.); see long (adj.). Related: Prolonged; prolonging; prolongable.
prolongation (n.): late 14c., from Old French prolongation (14c.), from Late Lation prolongationem (nominative prolongatio), noun of action from past participle stem of Latin prolongare "to prolong, extend," from Latin pro- "forth" (see pro-) + longus "long" (adj.); see long (adj.).
prom (n.): "student formal dance in celebration of graduation," 1894, American English shortened form of promenade (n.). Prom dress attested from 1975.
promenade (n.): 1560s, "leisurely walk," from Middle French promenade (16c.), from se promener "go for a walk," from Late Latin prominare "to drive (animals) onward," from pro- "forth" (see pro-) + minare "to drive (animals) with shouts," from minari "to threaten" (see menace (n.)).

Meaning "place for walking" is 1640s; specifically "walkway by the sea" late 18c.; British sense of "music hall favored by 'loose women and the simpletons who run after them'" is attested from 1863. Sense of "dance given by a school" is from 1887.
promenade (v.): "to make a promenade," 1580s, from promenade (n.). Related: Promenaded; promenading.
Promethean (adj.): 1580s, from Prometheus + -an. Before the introduction of modern matches (see lucifer), promethean was the name given (early 19c.) to small glass tubes full of sulphuric acid, surrounded by an inflammable mixture, which ignited when pressed and gave off light.
Prometheus: demigod (son of the Titan Iapetus) who made man from clay and stole fire from heaven and taught mankind its use, for which he was punished by Zeus by being chained to a rock in the Caucasus, where a vulture came every day and preyed on his liver. The name is Greek, and anciently was interpreted as literally "forethinker, foreseer," from promethes "thinking before," from pro- "before" (see pro-) + *methos, related to mathein "to learn," from enlargement of PIE root *men- "to think" (see mind (n.)). However Watkins suggests the second element is possibly from a base meaning "to steal," also found in Sanskrit mathnati "he steals."
promethium (n.): radioactive element, long one of the "missing elements," 1948, so called by discoverers Jacob Marinsky and Lawrence Glendenin, who detected it in 1945 in the fusion products of uranium while working on the Manhattan Project. From Prometheus, who stole fire from the gods and was punished for it, + element name ending -ium. "The name not only symbolizes the dramatic way in which the element may be produced in quantity as a result of man's harnessing of the energy of nuclear fission, but also warns man of the impending danger of punishment by the vulture of war." [Marinsky and Glendenin]
prominence (n.): 1590s, "projection," from obsolete French prominence (16c.), from Latin prominentia "a jutting out" (see prominent). Meaning "distinction, conspicuousness" is attested by 1827. As a type of solar phenomenon, from 1862.
prominent (adj.): mid-15c., "projecting, jutting out," from Latin prominentem (nominative prominens) "prominent," present participle of prominere "jut or stand out, be prominent, overhang," from pro- "before, forward" (see pro-) + -minere "project, jut out," which is related to mons "hill" (see mount (n.1)). Meaning "conspicuous" is from 1759; that of "notable, leading" is from 1849. Related: Prominently.
promiscuity (n.): 1834, "indiscriminate mixture," from French promiscuité (1752), from Latin promiscuus "mixed" (see promiscuous) + French -ité (see -ity). Sexual sense is from 1844. Earlier was promiscuousness (by 1773 general; 1808 sexual).
promiscuous (adj.): c. 1600, people or things, "mingled confusedly, grouped together without order, consisting of a disorderly mix; indiscriminate," from Latin promiscuus "mixed, indiscriminate, in common, without distinction," from pro- "forward" (see pro-) + miscere "to mix" (see mix (v.)). Meaning "indiscriminate in sexual relations" recorded by 1857, from promiscuity. The Latin adjective was used with conubia (such as between patricians and plebeians). Related: Promiscuously.
promise (n.): c. 1400, "a pledge, vow," from Old French promesse "promise, guarantee, assurance" (13c.) and directly from Latin promissum "a promise," noun use of neuter past participle of promittere "send forth; let go; foretell; assure beforehand, promise," from pro- "before" (see pro-) + mittere "to put, send" (see mission). The ground sense is "declaration made about the future, about some act to be done or not done."
promise (v.): c. 1400, from promise (n.). Related: Promised; promising. Promised land (1530s) is a reference to the land of Canaan promised to Abraham and his progeny (Hebrew xi:9, etc.; Greek ten ges tes epangelias).
promising (adj.): "showing signs of future excellence," c. 1600, present participle adjective from promise (v.). Related: Promisingly.
promisor (n.): 1790, agent noun in Latin form from promise (v.). Apparently restricted to legal use.
promissory (adj.): mid-15c., from Medieval Latin promissorius, from Latin promissus, past participle of promittere (see promise (n.)). Promissory note recorded by 1670s.
promnesia (n.): scientific name for the phenomenon of déjà vu, 1895, Modern Latin, from Greek pro- "before" (see pro-) + -mnesia "memory" (see amnesia).
promo (n.): 1958 (in "Billboard" headlines), shortening of promotion in the sense "advertising, publicity."
promontory (n.): 1540s, from Middle French promontoire (15c.) and directly from Medieval Latin promontorium, altered (by influence of Latin mons "mount, hill") from Latin promunturium "mountain ridge, headland," probably related to prominere "jut out" (see prominent).
promote (v.): late 14c., "to advance (someone) to a higher grade or office," from Old French promoter and directly from Latin promotus, past participle of promovere "move forward, advance; cause to advance, push onward; bring to light, reveal," from pro- "forward" (see pro-) + movere "to move" (see move (v.)). General sense of "to further the growth or progress of (anything)" is from 1510s. Related: Promoted; promoting.
promoter (n.): late 14c., "one who promotes" (the interest of someone), "supporter," agent noun from promote, and also from Old French promoteur and directly from Medieval Latin promotor. Specific financial sense of "one who leads in forming a company" is from 1876; sense of "one who organizes sporting or entertainment events" is attested from 1936.
promotion (n.): c. 1400, "advancement in rank or position," from Old French promocion "election, promotion" (14c., Modern French promotion) and directly from Latin promotionem (nominative promotio) "a moving forward," noun of action from past participle stem of promovere (see promote). Meaning "advertising, publicity" first recorded 1925.
promotional (adj.): 1869, "relating to promotion or advancement," from promotion + -al (1). From 1902 as "relating to advertising."
prompt (v.): mid-14c., prompten, from Latin promptus, past participle of promere "to bring forth," from pro- "forward" (see pro-) + emere "to take" (see exempt (adj.)). Theatrical sense of "to assist a speaker with lines" is first recorded early 15c. Related: Prompted; prompting.
prompt (n.): early 15c., "readiness," from Latin promptus (see prompt (v.)). Meaning "hint, act of prompting" is from 1590s. Computer sense attested by 1977.
prompt (adj.): early 15c., from Old French prompt and directly from Latin promptus "brought forth," hence "visible, apparent, evident," past participle of promere "to take or bring out or forth" (see prompt (v.)).Related: Promptly; promptitude.
prompter (n.): 1540s, agent noun from prompt (v.)). Earlier was promptator (mid-15c.).
promptness (n.): 1520s, from prompt (adj.) + -ness.
promulgate (v.): 1520s, from Latin promulgatus, past participle of promulgare "make publicly known, propose openly, publish," perhaps altered from provulgare, from pro- "forth" (see pro-) + vulgare "make public, publish." Or the second element might be from mulgere "to milk" (see milk (n.)), used metaphorically for "cause to emerge;" "a picturesque farmers' term used originally of squeezing the milk from the udder" [L.R. Palmer, "The Latin Language"]. Related: Promulgated; promulgating. The earlier verb in English was promulge (late 15c.).
promulgation (n.): c. 1600, from Middle French promulgation (14c.), from Latin promulgationem (nominative promulgatio) "a public announcement," noun of action from past participle stem of promulgare (see promulgate).
pronate: 1848 (adj.); 1819 (v.), from Late Latin pronatus, past participle of pronare "to bend forward," from pronus "prone" (see prone). Related: Pronated; pronating.
pronation (n.): 1660s, from French pronation, from Medieval Latin pronationem (nominative pronatio), noun of action from past participle stem of Late Latin pronare (see pronate).
prone (adj.): c. 1400, "naturally inclined to something, apt, liable," from Latin pronus "bent forward, leaning forward, bent over," figuratively "inclined to, disposed," perhaps from adverbial form of pro- "before, for, instead of" (see pro-) + ending as in infernus, externus. Meaning "lying face-down" is first recorded 1570s. Literal and figurative senses both were in Latin; figurative is older in English. Related: Proneness.
prong (n.): early 15c., prange "pointed instrument;" mid-15c., pronge "pain," from Anglo-Latin pronga "prong, pointed tool," of unknown origin, perhaps related to Middle Low German prange "stick, restraining device," prangen "to press, pinch." See also prod, which might be related. Prong-horned antelope is from 1815 (short form pronghorn attested from 1826).