Etymology
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second (n.1)

"one-sixtieth of a minute of degree," also "sixtieth part of a minute of time," late 14c. in geometry and astronomy, seconde, from Old French seconde, from Medieval Latin secunda, short for secunda pars minuta "second diminished part," the result of the second division of the hour by sixty (the first being the "prime minute," now simply the minute), from Latin secunda, fem. of secundus "following, next in time or order" (see second (adj.)).

The second hand of a clock, the pointer indicating the passage of seconds, is attested by 1759.

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quadrivium (n.)

"arithmetic, music, geometry, astronomy" (the four branches of mathematics, according to the Pythagoreans), by 1751, from Latin quadrivium, which meant "place where four roads meet, crossroads," from quadri- "four" (from PIE root *kwetwer- "four") + via "way, road, channel, course" (see via). Compare liberal arts, and also see trivium.

The adjective quadrivial is attested from mid-15c. in English with the sense of "belonging to the quadrivium," late 15c. with the sense of "having four roads, having four ways meeting in a point."

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mobile (n.)

early 15c. in astronomy, "outer sphere of the universe" (the primum mobile), from mobile (adj.); the artistic sense "abstract sculpture consisting of parts suspended so as to move," associated with Alexander Calder, is by 1939, perhaps a shortening of mobile sculpture (1936). Now-obsolete sense of "the common people, the rabble" (1670s, short for Latin mobile vulgus) led to mob (n.). Middle English had moble, moeble (mid-14c.) "movable goods, personal property," from Old French moble, meuble, from the Latin adjective, but in 16c. this was replaced by furniture.

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apogee (n.)
"point at which the moon is farthest from the earth," 1590s, from French apogée or directly from Latin apogaeum, from Greek apogaion (diastema) "(distance) away from the earth," from apogaion, neuter adjective, "from land," here in a specialized sense "away from the earth," from apo "off, away" (see apo-) + gaia/ge "earth" (see Gaia).

Figurative sense "climax, culmination" is from 1640s. A term from Ptolemaic astronomy, which regarded the earth as the center of the universe and applied the word to the sun and planets; for these bodies it was displaced in the Copernican system by aphelion. Adjective forms are apogeal, apogean, apogeic.
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Ophiuchus 

ancient constellation (representing Aesculapius), 1650s, from Latin, from Greek ophioukhos, literally "holding a serpent," from ophis "serpent" (see ophio-) + stem of ekhein "to hold, have, keep" (from PIE root *segh- "to hold").

Translated in Latin as Anguitenens and Serpentarius. Milton's "Ophiuchus huge in th' Arctick Sky" ("Paradise Lost") is a rare (minor) lapse for a poet who generally knew his astronomy; the constellation actually straddles the celestial equator, and, as its modern boundaries are drawn, dips into the zodiac: The sun passes through Ophiuchus from about Nov. 30 to Dec. 18. The serpent now is treated as a separate constellation.

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perpendicular (adj.)

late 15c., perpendiculer, of a line, "lying at right angles to the horizon" (in astronomy, navigation, etc.), from an earlier adverb (late 14c.), "at right angles to the horizon," from Old French perpendiculer, from Late Latin perpendicularis "vertical, as a plumb line," from Latin perpendiculum "plumb line," from perpendere "balance carefully," from per "thoroughly" (see per) + pendere "to hang, cause to hang; weigh" (from PIE root *(s)pen- "to draw, stretch, spin").

The meaning "perfectly vertical" is by 1590s. As a noun, "a line that meets another line or plane at right angles," from 1570s. The earlier noun was perpendicle (c. 1400). Related: Perpendicularly; perpendicularity.

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zone (n.)

late 14c., from Latin zona "geographical belt, celestial zone," from Greek zōnē "a belt, the girdle worn by women at the hips," from zōnnynai "to gird," from PIE root *yos- "to gird" (source also of Avestan yasta- "girt," Lithuanian juosiu, juosti "to gird," Old Church Slavonic po-jasu "girdle"). The 10c. Anglo-Saxon treatise on astronomy translates Latin quinque zonas as fyf gyrdlas.

Originally one of the five great divisions of the earth's surface (torrid, temperate, frigid; separated by tropics of Cancer and Capricorn and Arctic and Antarctic circles); meaning "any discrete region" is first recorded 1822. Zone defense in team sports is recorded from 1927.

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alpha (n.)
c. 1300, from Latin alpha, from Greek alpha, from Hebrew or Phoenician aleph (see aleph). The Greeks added -a because Greek words cannot end in most consonants. Sense of "beginning of anything" is from late 14c., often paired with omega (the last letter in the Greek alphabet, representing "the end"); sense of "first in a sequence" is from 1620s. In astronomy, the designation of the brightest star of each constellation (the use of Greek letters in star names began with Bayer's atlas in 1603). Alpha male was in use by c. 1960 among scientists studying animals; applied to humans in society from c. 1992.
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parapsychology (n.)

"the study of phenomena outside the sphere of orthodox psychology," by 1923, from German para-psychologie; see para- (1) "beside" + psychology. Related: Parapsychological.

Similarly, [Prof. Hans Driesch] includes under "parapsychology" such phenomena as telepathy and clairvoyance, which he regards as mere extensions from ordinary mental phenomena, rather than as fundamentally different processes. He believes that the same orderly process by which unclassified and diverse processes have been systematized,—alchemy becoming chemistry, astrology becoming astronomy,—is at work now,—to make, in place of the mysterious tradition of Occultism, a science which will really be an extension from scientific psychology and biology. ["Journal of the American Society for Psychical Research," April 1923]
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apparent (adj.)
late 14c., "indisputable, clearly understood;" c. 1400, "easily seen or perceived," from Old French aparant "evident, obvious, visible," from Latin apparentem (nominative apparens) "visible, manifest," present participle of apparere "appear, come in sight" (see appear).

First attested in phrases such as heir apparent (see heir). Meaning "superficial, spurious" is from c. 1400; that of "appearing to the senses or mind but not necessarily real" is from 1640s. Apparent magnitude in astronomy (how bright a heavenly body looks from earth, as opposed to absolute magnitude, which is how bright it really is) is attested from 1875. Middle English had noun forms apparence, apparency, but both are obsolete from 17c.
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