an imaginary belt in the heavens that encompasses the apparent paths of all the principal planets except Pluto, has the ecliptic1 (apparent annual path of the sun) as its central line, and is divided into twelve constellations or signs each taken for astrological purposes to extend 30° of longitude
zodiacal /zohʹdie·əkl, zə-/ adj
[Middle English via early French and Latin zodiacus, from Greek zōidiakos, from zōidion carved figure, sign of the zodiac, dimin. of zōion living being, figure]