Word Origin & History
sphere
c.1533, restored spelling of M.E. spere (c.1300) "space, conceived as a hollow globe about the world," from O.Fr. espere (13c.), from L. sphæra "globe, ball, celestial sphere," from Gk. sphaira "globe, ball," of unknown origin. Sense of "ball, body of globular form" is from 1388. Medieval astronomical meaning "one of the 8 (later 10) concentric, transparent, hollow globes believed to revolve around the earth and carry the heavenly bodies" is from c.1374; the supposed harmonious sound they made rubbing against one another was the music of the spheres (c.1381). Meaning "range of something" is first recorded 1601 (e.g. sphere of influence, 1885, in ref. to British-German colonial rivalry in Africa). A spherical number (1646) is one whose powers always terminate in the same digit as the number itself (5,6, and 10 are the only ones).