The definition of the Milky Way is a galaxy 100,000 light years in diameter, 25,000 light years from its center and 1,000 light years thick.
An example of the Milky Way is the galaxy that holds the Solar System in which the Earth is located.
See Milky Way in Webster's New World College Dictionary
Origin: transl. of L via lactea, transl. of Gr galaxias kyklos: see galaxy
See Milky Way in American Heritage Dictionary 4
Origin: Middle English
Origin: , translation of Latin via lactea
Origin: : via, way
Origin: + lactea
Origin: , feminine of lacteus, milky.
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