1. (cosmology) one million parsecs; 3.08568 x 10^22m or 3.262 million light years, roughly the distance from the Milky Way to the nearest galaxy (0.77Mpc to Andromeda)
   "Distances between galaxy clusters are often measured in megaparsecs";
   - Mpc

Derived forms: megaparsecs

Encyclopedia: Megaparsec