noun

• (astrology) The belt-like region of the celestial sphere, approximately eight degrees north and south of the ecliptic, which includes the apparent path of the sun, moon, and visible planets.
  "Tremulous on the bladed graſs ſhone bright the pearly drops, like an aſſembly of ſparkling ſtars dancing on the plains of the zodiac; vocal was every bending ſpray, every reed was inſpired, each vvarbling throat ſeemed to emulate the melodious voice of the bird of a thouſand ſongs."
• (astrology) The twelve equal divisions of the zodiacal region into signs or houses, each named for a prominent constellation in the region.
• (astronomy) The ecliptic: the belt-like region of the celestial sphere corresponding to the apparent path of the sun over the course of a year.
• (countable) A circle decorated with the signs of the zodiac.