The Collaborative International Dictionary of English v.0.48:

Megarian \Me*ga"ri*an\, Megaric \Me*gar"ic\, a.
   Belonging, or pertaining, to Megara, a city of ancient
   Greece.
   [1913 Webster]

   Megarian school, or Megaric school, a school of
      philosophy established at Megara, after the death of
      Socrates, by his disciples, and remarkable for its logical
      subtlety.
      [1913 Webster]