Source : Webster's Revised Unabridged Dictionary (1913)

Evection \E*vec"tion\ [L. evectio a going up, fr. evehere to
   carry out; e out + vehere to carry: cf. F ['e]vection.]
   1. The act of carrying up or away; exaltation. [Obs.] --Bp.
      Pearson.

   2. (Astron.)
      (a) An inequality of the moon's motion is its orbit to the
          attraction of the sun, by which the equation of the
          center is diminished at the syzygies, and increased at
          the quadratures by about 1[deg] 20'.
      (b) The libration of the moon. --Whewell.