Etymology
Advertisement
chakra (n.)

1888 in yoga sense "a spiritual center of power in the human body," from Sanskrit cakra "circle, wheel," from PIE root *kwel- (1) "revolve, move round."

Related entries & more 
Advertisement
whirl (v.)
c. 1300, probably from Old Norse hvirfla "to go round, spin," related to hvirfill "circle, ring, crown," and to Old English hweorfan "to turn" (see wharf). Related: Whirled; whirling. Whirlybird "helicopter" is from 1951.
Related entries & more 
chukker (n.)

also chucker, chukka, "period in a polo game," 1898, from Hindi chakkar, from Sanskrit cakra "circle, wheel," from PIE root *kwel- (1) "revolve, move round."

Related entries & more 
orbicular (adj.)

"round, circular, spherical, having the shape of an orb," mid-15c., from Old French orbiculaire "round, circular," or directly from Late Latin orbicularis "circular, orbicular," from Latin orbiculus, diminutive of orbis "circle" (see orb). Related: Orbicularity.

Related entries & more 
octant (n.)

instrument for making angular measurements in navigation or astronomy, 1731, from Late Latin octans "the eighth part," from octo "eight" (see octa-) on analogy of quadrant. In geometry, "the eighth part of a circle," by 1750.

Related entries & more 
Advertisement
radius (n.)

1590s, "cross-shaft, straight rod or bar," from Latin radius "staff, stake, rod; spoke of a wheel; ray of light, beam of light; radius of a circle," a word of unknown origin. Perhaps related to radix "root," but de Vaan finds that "unlikely." The classical plural is radii

The geometric sense of "straight line drawn from the center of a circle to the circumference" is recorded from 1650s. Meaning "circular area of defined distance around some place" is attested from 1853. As the name of the shorter of the two bones of the forearm from 1610s in English (the Latin word had been used thus by the Romans).

Related entries & more 
roundabout (adv.)

mid-14c., roundeaboute, "by a circuitous route," also "on all sides, all about," from round (adv.), for which see round (adj.), + about. As an adjective, "in a ring or circle," by mid-14c. By late 15c. (Caxton) as a preposition. As an adjective from c. 1600. Noun sense of "traffic circle" is attested from 1927. It was used earlier of other things, such as "circular course or object" (1530s), "a plump, rounded figure" (1812), "a detour" (1755), "a merry-go-round" (1763). Related: Roundaboutness.

Related entries & more 
gyro (n.)
sandwich made from roasted lamb, 1971, originally the meat itself, as roasted on a rotating spit, from Modern Greek gyros "a circle" (see gyre (n.)). Mistaken in English for a plural and shorn of its -s.
Related entries & more 
zodiac (n.)
late 14c., from Old French zodiaque, from Latin zodiacus "zodiac," from Greek zodiakos (kyklos) "zodiac (circle)," literally "circle of little animals," from zodiaion, diminutive of zoion "animal" (from PIE root *gwei- "to live").

Libra is not an animal, but it was not a zodiac constellation to the Greeks, who reckoned 11 but counted Scorpio and its claws (including what is now Libra) as a "double constellation." Libra was figured back in by the Romans. In Old English the zodiac was twelf tacna "the twelve signs," and in Middle English also Our Ladye's Waye and the Girdle of the Sky.
Related entries & more 
logical (adj.)
early 15c., "based on reason, according to the principles of logic," from logic + -al (1). Meaning "pertaining to logic" is c. 1500. Attested from 1860 as "following as a reasonable consequence." Related: Logically. Logical positivism, in reference to the ideas of the Vienna Circle of philosophers, is from 1931.
Related entries & more 

Page 5