also flash-light, 1886, "on-and-off signal light in a light-house, etc.," from flash (v.) + light (n.). As the word for a photographer's light-emitting preparation, 1892 (flash-lamp in this sense is by 1890). From 1905 as as a handheld, pocket-sized electric illumination device, the American English word for what the British might call an electric torch.
(plural lustra), "ceremonial purification of the Roman people every five years," 1580s, from Latin lustrum "a purificatory sacrifice, ceremony of purification; five-year period," from Proto-Italic *lustro- "expiation," which is of uncertain origin. Perhaps [OED] from root of luere "to wash" (from PIE root *leue- "to wash"). Or [Watkins, Klein], based on a possible earlier meaning "illumination," from PIE *leuk-stro-, from root *leuk- "light, brightness." De Vaan prefers as most likely the explanation "that lustrum was derived from *luH- 'to set free'," with suffix *-stro- also found in monstrum, etc.
1580s, "a reduced image, anything represented on a greatly reduced scale," especially a painting of very small dimensions, from Italian miniatura "manuscript illumination or small picture," from past participle of miniare "to illuminate a manuscript," from Latin miniare "to paint red," from minium "red lead," used in ancient times to make red ink, a word said to be of Iberian origin. Sense development is because pictures in medieval manuscripts were small, but no doubt there was influence as well from the similar-sounding Latin words that express smallness: minor, minimus, minutus, etc.
c. 1400, "a shining;" early 15c., "a manifestation;" mid-15c., "a spiritual illumination," from Old French illustration "apparition, appearance" (13c.) and directly from Latin illustrationem (nominative illustratio) "vivid representation" (in writing), literally "an enlightening," from past participle stem of illustrare "light up, make light, illuminate;" figuratively "make clear, disclose, explain; adorn, render distinguished," from assimilated form of in- "in" (from PIE root *en "in") + lustrare "make bright, illuminate," from suffixed form of PIE root *leuk- "light, brightness." Mental sense of "act of making clear in the mind" is from 1580s. Meaning "an illustrative picture" is from 1816.
"any mode of thought or life in which reliance is placed upon a spiritual illumination believed to transcend ordinary powers of understanding," 1736, from mystic (adj.) + -ism. Often especially in a religious sense, and since the Enlightenment a term of reproach, implying self-delusion or dreamy confusion of thought.
Mysticism and rationalism represent opposite poles of theology, rationalism regarding the reason as the highest faculty of man and the sole arbiter in all matters of religious doctrine; mysticism, on the other hand, declaring that spiritual truth cannot be apprehended by the logical faculty, nor adequately expressed in terms of the understanding. [Century Dictionary]
"brightness, radiant energy, that which makes things visible," Old English leht (Anglian), leoht (West Saxon), "light, daylight; spiritual illumination," from Proto-Germanic *leukhtam (source also of Old Saxon lioht, Old Frisian liacht, Middle Dutch lucht, Dutch licht, Old High German lioht, German Licht, Gothic liuhaþ "light"), from PIE root *leuk- "light, brightness."
The -gh- was an Anglo-French scribal attempt to render the Germanic hard -h- sound, which has since disappeared from this word. The figurative spiritual sense was in Old English; the sense of "mental illumination" is first recorded mid-15c. Meaning "something used for igniting" is from 1680s. Meaning "a consideration which puts something in a certain view" (as in in light of) is from 1680s. Short for traffic light from 1938. Quaker use is by 1650s; New Light/Old Light in church doctrine also is from 1650s. Meaning "person eminent or conspicuous" is from 1590s. A source of joy or delight has been the light of (someone's) eyes since Old English:
Ðu eart dohtor min, minra eagna leoht [Juliana].
Phrases such as according to (one's) lights "to the best of one's natural or acquired capacities" preserve an older sense attested from 1520s. To figuratively stand in (someone's) light is from late 14c. To see the light "come into the world" is from 1680s; later as "come to full realization" (1812). The rock concert light-show is from 1966. To be out like a light "suddenly or completely unconscious" is from 1934.
mid-15c., "lamp, light-giver, source of light," from Old French luminarie (12c.), "lamp, lights, lighting; candles; brightness, illumination," from Late Latin luminare "light, torch, lamp, heavenly body," literally "that which gives light," from Latin lumen (genitive luminis) "light, source of light, daylight, the light of the eye; distinguished person, ornament, glory," related to lucere "to shine," from suffixed (iterative) form of PIE root *leuk- "light, brightness."
From late 15c. as "celestial body." Sense of "notable person" is first recorded 1690s, though the Middle English word also had a figurative sense of "source of spiritual light, example of holiness" (mid-15c.). As an adjective, "pertaining to light," from 1794 but this is rare.
Old English great "big, tall, thick, stout, massive; coarse," from West Germanic *grauta- "coarse, thick" (source also of Old Saxon grot, Old Frisian grat, Dutch groot, German groß "great"). If the original sense was "coarse," it is perhaps from PIE root *ghreu- "to rub, grind," via the notion of "coarse grain," then "coarse," then "great;" but "the connextion is not free from difficulty" [OED].
It took over much of the sense of Middle English mickle, and itself now is largely superseded by big and large except in reference to non-material things. In the sense of "excellent, wonderful" great is attested from 1848.
Great White Way "Broadway in New York City" is from 1901, in reference to brilliant street illumination. The Great Lakes of North America so called by 1726, perhaps 1690s. Great Spirit "high deity of the North American Indians," 1703, originally translates Ojibwa kitchi manitou. The Great War originally (1887) referred to the Napoleonic Wars, later (1914) to what we now call World War I (see world).
"The Great War" — as, until the fall of France, the British continued to call the First World War in order to avoid admitting to themselves that they were now again engaged in a war of the same magnitude. [Arnold Toynbee, "Experiences," 1969]
Also formerly with a verb form, Old English greatian "to become enlarged," Middle English greaten "to become larger, increase, grow; become visibly pregnant," which became archaic after 17c.
late Old English niht (West Saxon neaht, Anglian næht, neht) "the dark part of a day; the night as a unit of time; darkness," also "absence of spiritual illumination, moral darkness, ignorance," from Proto-Germanic *nahts (source also of Old Saxon and Old High German naht, Old Frisian and Dutch nacht, German Nacht, Old Norse natt, Gothic nahts).
The Germanic words are from PIE *nekwt- "night" (source also of Greek nyx "a night," Latin nox, Old Irish nochd, Sanskrit naktam "at night," Lithuanian naktis "night," Old Church Slavonic nosti, Russian noch', Welsh henoid "tonight"), according to Watkins, probably from a verbal root *neg- "to be dark, be night." For spelling with -gh- see fight. The vowel indicates that the modern English word derives from oblique cases (genitive nihte, dative niht).
The fact that the Aryans have a common name for night, but not for day (q.v.), is due to the fact that they reckoned by nights. [Weekley]
Thus in Old English combinations night was "the night before (a certain day or feast day);" compare German Weihnachten "Christmas," literally "holy night." In early times, the day was held to begin at sunset, so Old English monanniht "Monday night" was the night before Monday, or what we would call Sunday night; so saeterniht "Friday night." The Greeks, by contrast, counted their days by mornings.
To work nights preserves the Old English genitive of time. Night soil "excrement" (1770) is so called because it was removed (from cesspools, etc.) after dark. Night train is attested from 1838; night-school from 1520s; night-life "habitual nocturnal carousing" is attested from 1852.