mid-14c., "state or fact of knowing; what is known, knowledge (of something) acquired by study; information;" also "assurance of knowledge, certitude, certainty," from Old French science "knowledge, learning, application; corpus of human knowledge" (12c.), from Latin scientia "knowledge, a knowing; expertness," from sciens (genitive scientis) "intelligent, skilled," present participle of scire "to know."
The original notion in the Latin verb probably is "to separate one thing from another, to distinguish," or else "to incise." This is related to scindere "to cut, divide" (from PIE root *skei- "to cut, split;" source also of Greek skhizein "to split, rend, cleave," Gothic skaidan, Old English sceadan "to divide, separate").
OED writes that the oldest English sense of the word now is restricted to theology and philosophy. From late 14c. in English as "book-learning," also "a particular branch of knowledge or of learning, systematized knowledge regarding a particular group of objects;" also "skillfulness, cleverness; craftiness." From c. 1400 as "experiential knowledge;" also "a skill resulting from training, handicraft; a trade."
From late 14c. in the more specific sense of "collective human knowledge," especially that gained by systematic observation, experiment, and reasoning. The modern (restricted) sense of "body of regular or methodical observations or propositions concerning a particular subject or speculation" is attested by 1725; in 17c.-18c. this commonly was philosophy.
The sense of "non-arts studies" is attested from 1670s. The distinction is commonly understood as between theoretical truth (Greek epistemē) and methods for effecting practical results (tekhnē), but science sometimes is used for practical applications and art for applications of skill.
The predominant modern use, "natural and physical science," generally restricted to study of the phenomena of the material universe and its laws, is by mid-19c.
To blind (someone) with science "confuse by the use of big words or complex explanations" is attested from 1937, originally noted as a phrase from Australia and New Zealand.
The men who founded modern science had two merits which are not necessarily found together: Immense patience in observation, and great boldness in framing hypotheses. The second of these merits had belonged to the earliest Greek philosophers; the first existed, to a considerable degree, in the later astronomers of antiquity. But no one among the ancients, except perhaps Aristarchus, possessed both merits, and no one in the Middle Ages possessed either. [Bertrand Russell, "A History of Western Philosophy," 1945]
Science, since people must do it, is a socially embedded activity. It progresses by hunch, vision, and intuition. Much of its change through time does not record a closer approach to absolute truth, but the alteration of cultural contexts that influence it so strongly. Facts are not pure and unsullied bits of information; culture also influences what we see and how we see it. Theories, moreover, are not inexorable inductions from facts. The most creative theories are often imaginative visions imposed upon facts; the source of imagination is also strongly cultural. [Stephen Jay Gould, introduction to "The Mismeasure of Man," 1981]
1530s spelling alteration (see wh-) of Middle English hore, from Old English hore "prostitute, harlot," from Proto-Germanic *hōran-, fem. *hōrā- (source also of Old Frisian hor "fornication," Old Norse hora "adulteress," Danish hore, Swedish hora, Dutch hoer, Old High German huora "prostitute;" in Gothic only in the masc. hors "adulterer, fornicator," also as a verb, horinon "commit adultery"), probably etymologically "one who desires," from PIE root *ka- "to like, desire," which in other languages has produced words for "lover; friend."
Whore itself is perhaps a Germanic euphemism for a word that has not survived. The Old English vowel naturally would have yielded *hoor, which is the pronunciation in some dialects; it might have shifted by influence of Middle English homonym hore "physical filth, slime," also "moral corruption, sin," from Old English horh. The wh- form became current 16c. A general term of abuse for an unchaste or lewd woman (without regard to money) from at least c. 1200. Of male prostitutes from 1630s. Whore of Babylon is from Revelation xvii.1, 5, etc. In Middle English with occasional plural forms horen, heoranna.
The word, with its derivatives, is now avoided polite speech; its survival in literature, so as it survives, is due to the fact that it is a favorite word with Shakspere (who uses it, with its derivatives, 99 times) and is common in the authorized English version of the Bible ... though the American revisers recommended the substitution of harlot as less gross .... [Century Dictionary]
Some equivalent words in other languages also derive from sources not originally pejorative, such as Bohemian nevestka, diminutive of nevesta "bride;" Dutch deern, German dirne originally "girl, lass, wench;" also perhaps Old French pute, perhaps literally "girl," fem. of Vulgar Latin *puttus (but perhaps rather from Latin putidus "stinking;" see poontang). Welsh putain "whore" is from French, probably via Middle English. Among other languages, Greek porne "prostitute" is related to pernemi "sell," with an original notion probably of a female slave sold for prostitution; Latin meretrix is literally "one who earns wages" (source of Irish mertrech, Old English miltestre "whore, prostitute").
The vulgar Roman word was scortum, literally "skin, hide." Another term was lupa, literally "she-wolf" (preserved in Spanish loba, Italian lupa, French louve; see wolf (n.)). And of course there was prostituta, literally "placed in front," thus "publicly exposed," from the fem. past participle of prostituere (see prostitute (n.)). Another Old Norse term was skækja, which yielded Danish skøge, Swedish sköka; probably from Middle Low German schoke, which is perhaps from schode "foreskin of a horse's penis," perhaps with the sense of "skin" (compare Latin scortum) or perhaps via an intermediary sense of "vagina." Spanish ramera, Portuguese rameira are from fem. form of ramero "young bird of prey," literally "little branch," from ramo "branch." Breton gast is cognate with Welsh gast "bitch," of uncertain origin. Compare also strumpet, harlot.
Old Church Slavonic ljubodejica is from ljuby dejati "fornicate," a compound from ljuby "love" + dejati "put, perform." Russian bljad "whore" derives from Old Church Slavonic bladinica, from bladu "fornication." Polish nierządnica is literally "disorderly woman." Sanskrit vecya is a derivation of veca- "house, dwelling," especially "house of ill-repute, brothel." Another term, pumccali, means literally "one who runs after men." Avestan jahika is literally "woman," but only of evil creatures; another term is kunairi, from pejorative prefix ku- + nairi "woman."