The Collaborative International Dictionary of English v.0.48:

Migrate \Mi"grate\, v. i. [imp. & p. p. Migrated; p. pr. & vb.
   n. Migrating.] [L. migratus, p. p. of migrare to migrate,
   transfer.]
   [1913 Webster]
   1. To remove from one country or region to another, with a
      view to residence; to change one's place of residence; to
      remove; as, the Moors who migrated from Africa into Spain;
      to migrate to the West.
      [1913 Webster]

   2. To pass periodically from one region or climate to another
      for feeding or breeding; -- said of certain birds, fishes,
      and quadrupeds.
      [1913 Webster]