late 14c., "hallowed, consecrated, or made holy by association with divinity or divine things or by religious ceremony or sanction," past-participle adjective from a now-obsolete verb sacren "to make holy" (c. 1200), from Old French sacrer "consecrate, anoint, dedicate" (12c.) or directly from Latin sacrare "to make sacred, consecrate; hold sacred; immortalize; set apart, dedicate," from sacer (genitive sacri) "sacred, dedicated, holy, accursed." OED writes that, in sacred, "the original ppl. notion (as pronunciation indicates) disappeared from the use of the word, which is now nearly synonymous with L. sacer."
This is from Old Latin saceres, from PIE root *sak- "to sanctify." Buck groups it with Oscan sakrim, Umbrian sacra and calls it "a distinctive Italic group, without any clear outside connections." De Vaan has it from a PIE root *shnk- "to make sacred, sanctify," and finds cognates in Hittite šaklai "custom, rites," zankila "to fine, punish." Related: Sacredness. The Latin nasalized form is sancire "make sacred, confirm, ratify, ordain" (as in saint, sanction). An Old English word for "sacred" was godcund.
The meaning "of or pertaining to religion or divine things" (opposed to secular or profane) is by c. 1600. The transferred sense of "entitled to respect or reverence" is from 1550s. Sacred cow as an object of Hindu veneration is by 1793; its figurative sense of "one who or that which must not be criticized" is in use by 1910 in U.S. journalism, reflecting Western views of Hinduism. Sacred Heart "the heart of Jesus as an object of religious veneration" is by 1823, short for Sacred Heart of Jesus or Mary.
Also formerly in English "a shivering," especially as a symptom of disease or in reaction to a sour or bitter taste (1530s); "erection of the hairs on the skin" (1650s); "a ruffling as of water surface" (1630s). As a genre in film, 1934. Chamber of horrors originally (1849) was a gallery of notorious criminals in Madame Tussaud's wax exhibition. Other noun forms are horribility (14c., now rare or disused), horribleness (late 14c.), horridity (1620s), horridness (1610s).
late 13c., "honor, respect, deference (shown to someone), esteem heightened by awe," also of places or holy objects, from Old French reverence "respect, awe" and directly from Latin reverentia "awe, respect," from revereri "to stand in awe of, respect, honor, fear, be afraid of; revere," from re-, here perhaps an intensive prefix (see re-), + vereri "stand in awe of, fear, respect" (from PIE root *wer- (3) "perceive, watch out for").
Reverence is nearly equivalent to veneration, but expresses something less of the same emotion. It differs from awe in that it is not akin to the feeling of fear, dread, or terror, while also implying a certain amount of love or affection. We feel reverence for a parent and for an upright magistrate, but we stand in awe of a tyrant. [Century Dictionary]
From late 14c. as "state of being revered or venerated." As a respectful form of address, with possessive pronoun, to a clergyman or ecclesiastic, late 14c. (Gower), "latterly only used by the lower classes, esp. in Ireland" [OED].
Old English locian "use the eyes for seeing, gaze, look, behold, spy," from West Germanic *lokjan (source also of Old Saxon lokon "see, look, spy," Middle Dutch loeken "to look," Old High German luogen, German dialectal lugen "to look out"), a word of unknown origin. Breton lagud "eye" has been suggested as a possible cognate.
In Old English, usually with on; the use of at began 14c. As a word to call attention, c. 1200 (look out! "take notice" is from mid-15c.). Meaning "seek, search out" is c. 1300; meaning "to have a certain appearance, express or manifest by looks" is from c. 1400. Of objects, "to face in a certain direction," late 14c. To look like "have the appearance of" is from mid-15c. Look after "take care of" is from late 14c., earlier "to seek" (c. 1300), "to look toward" (c. 1200). Look into "investigate" is from 1580s. To look forward "anticipate" is c. 1600; especially "anticipate with pleasure" from mid-19c. To look over "scrutinize" is from mid-15c.
Look up is from c. 1200 in literal sense "raise the eyes;" as "research in books or papers" from 1690s. To look up to "regard with respect and veneration" is from 1719. To look down upon in the figurative sense "regard as beneath one" is from 1711; to look down one's nose is from 1921. To not look back "make no pauses" is colloquial, first attested 1893. In look sharp (1711), sharp originally was an adverb, "sharply." To look around "search about, look round" is from 1883.