sphereyoudaoicibaDictYouDict[sphere 词源字典]
sphere: [17] Sphere goes back ultimately to Greek sphaira, a word of uncertain origin, which reached English via Latin sphaera or sphēra and Old French espere. Amongst the theories put forward to account for its ancestry are that it was derived from Greek sphurás ‘fall of dung, round pellet of dung, pill’, which has relatives in Lithuanian spira ‘sheep-dung’ and modern Icelandic sperthill ‘goat-dung’; and that it is related to Greek spaírein ‘quiver’ and Sanskrit sphur- ‘spring, quiver, trouble’. It metaphorical use in English for ‘area of activity’ dates from the early 17th century.
[sphere etymology, sphere origin, 英语词源]
sphere (n.)youdaoicibaDictYouDict
mid-15c., Latinized spelling of Middle English spere (c. 1300) "cosmos; space, conceived as a hollow globe about the world," from Anglo-French espiere, Old French espere (13c., Modern French sphère), from Latin sphaera "globe, ball, celestial sphere" (Medieval Latin spera), from Greek sphaira "globe, ball, playing ball, terrestrial globe," of unknown origin.

From late 14c. in reference to any of the supposed concentric, transparent, hollow, crystalline globes of the cosmos believed to revolve around the earth and contain the planets and the fixed stars; the supposed harmonious sound they made rubbing against one another was the music of the spheres (late 14c.). Also from late 14c. as "a globe; object of spherical form, a ball," and the geometric sense "solid figure with all points equidistant from the center." Meaning "range of something, place or scene of activity" is first recorded c. 1600 (as in sphere of influence, 1885, originally in reference to Anglo-German colonial rivalry in Africa).