1650s, "general science or theory of the material universe as an ordered whole," from Modern Latin cosmologia, from Greek kosmos (see cosmos) + -logia "discourse" (see -logy). By 1753 as "the branch of metaphysics which discusses the ultimate philosophical problems relating to the existence of the universe." Related: Cosmologist.
They cannot scare me with their empty spaces
Between stars—on stars where no human race is.
I have it in me so much nearer home
To scare myself with my own desert places.
[Robert Frost, from "Desert Places," 1936]
c. 1500, a back-formation from intelligence or else from Latin intelligentem (nominative intelligens), present participle of intelligere. Intelligent design, as a name for an alternative to atheistic cosmology and the theory of evolution, is from 1999. Related: Intelligently.
1590s, "situated under the moon," hence "earthly, mundane" (old cosmology), from Modern Latin sublunaris, from sub "under, beneath" (see sub-) + lunaris (see lunar). It owes its special sense to the old cosmology of heavenly spheres and ultimately to Aristotle:
The treatise On the Heavens sets forth a pleasant and simple theory. Things below the moon are subject to generation and decay; from the moon upwards, everything is ungenerated and indestructible. [Bertrand Russell, "A History of Western Philosophy"]
in Germanic cosmology, "the abode of the human race, the world inhabited by men" (opposed to Asgard, the abode of the gods), by 1770, from Old Norse miðgarðr, from mið "mid" (from PIE root *medhyo- "middle") + Proto-Germanic *gardoz "enclosure, tract" (from PIE root *gher- (1) "to grasp, enclose;" compare yard (n.1)). The Old English cognate was middangeard, which later was folk-etymologized as Middle Earth.
"empyreal," mid-14c. (as empyre), probably via Medieval Latin empyreus, from Greek empyros "fiery," from assimilated form of en (see en- (2)) + pyr "fire" (from PIE root *paewr- "fire"). As an adjective in English from early 15c. The etymological sense is "formed of pure fire or light." In ancient Greek cosmology, the highest heaven, the sphere of pure fire; later baptized with a Christian sense of "abode of God and the angels."
late 14c., "upper regions of space," from Old French ether (12c.) and directly from Latin aether "the upper pure, bright air; sky, firmament," from Greek aithēr "upper air; bright, purer air; the sky" (opposed to aēr "the lower air"), from aithein "to burn, shine," from PIE *aidh- "to burn" (see edifice).
In ancient cosmology, the element that filled all space beyond the sphere of the moon, constituting the substance of the stars and planets. Conceived of as a purer form of fire or air, or as a fifth element. From 17c.-19c., it was the scientific word for an assumed "frame of reference" for forces in the universe, perhaps without material properties. The concept was shaken by the Michelson-Morley experiment (1887) and discarded early 20c. after the Theory of Relativity won acceptance, but before it went it gave rise to the colloquial use of ether for "the radio" (1899).
The name also was bestowed c. 1730 (Frobenius; in English by 1757) on a volatile chemical compound known since 14c. for its lightness and lack of color (its anesthetic properties weren't fully established until 1842).
Old English woruld, worold "human existence, the affairs of life," also "a long period of time," also "the human race, mankind, humanity," a word peculiar to Germanic languages (cognates: Old Saxon werold, Old Frisian warld, Dutch wereld, Old Norse verold, Old High German weralt, German Welt), with a literal sense of "age of man," from Proto-Germanic *weraldi-, a compound of *wer "man" (Old English wer, still in werewolf; see virile) + *ald "age" (from PIE root *al- (2) "to grow, nourish").
Originally "life on earth, this world (as opposed to the afterlife)," sense extended to "the known world," then to "the physical world in the broadest sense, the universe" (c. 1200). In Old English gospels, the commonest word for "the physical world," was Middangeard (Old Norse Midgard), literally "the middle enclosure" (see yard (n.1)), which is rooted in Germanic cosmology. Greek kosmos in its ecclesiastical sense of "world of people" sometimes was rendered in Gothic as manaseþs, literally "seed of man." The usual Old Norse word was heimr, literally "abode" (see home). Words for "world" in some other Indo-European languages derive from the root for "bottom, foundation" (such as Irish domun, Old Church Slavonic duno, related to English deep); the Lithuanian word is pasaulis, from pa- "under" + saulė "sun."
Original sense in world without end, translating Latin saecula saeculorum, and in worldly. Latin saeculum can mean both "age" and "world," as can Greek aiōn. Meaning "a great quantity or number" is from 1580s. Out of this world "surpassing, marvelous" is from 1928; earlier it meant "dead." World Cup is by 1951; U.S. baseball World Series is by 1893 (originally often World's Series). World power in the geopolitical sense first recorded 1900. World-class is attested from 1950, originally of Olympic athletes.