chromosphere n.

in reference to color, "intensity of distinctive hue, degree of departure of a color-sensation from that of white or gray," 1889, from Latinized form of Greek khrōma "surface of the body, skin, color of the skin," also used generically for "color" and, in plural, "ornaments, makeup, embellishments," a verbal noun from khroizein "to color, stain, to touch the surface of the body," khrosthenai "to take on a color or hue," from khros, khroia "surface of the body, skin."

Beekes considers this noun to be of uncertain origin. It sometimes is explained as being somehow from PIE *ghreu- "to rub, grind" (see grit (n.)).

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," a word 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).