Word Study
zodiacal
CIDE DICTIONARY
zodiacal, a. [Cf. F. zodiacal.].
Of or pertaining to the zodiac; situated within the zodiac; as, the zodiacal planets. [1913 Webster]
OXFORD DICTIONARY
zodiacal, adj. of or in the zodiac.
Idiom
zodiacal light a luminous area of sky shaped like a tall triangle occasionally seen in the east before sunrise or in the west after sunset, esp. in the Tropics.
Etymology
F (as ZODIAC)
For further exploring for "zodiacal" in Webster Dictionary Online