The Collaborative International Dictionary of English v.0.48:

faraday \far"a*day\, n. [From Michael Faraday, the English
   electrician.] (Elec.)
   the quantity of electric charge that, passed though an ionic
   solution, will cause electrolysis of one equivalent of ions;
   it is equal to about 96,490 coulombs. The number of univalent
   metal ions (such as silver in a silver nitrate solution)
   which would be deposited as free metal by such a current is
   Avogadro's number, 6.023 x 10^23.
   [PJC]

WordNet (r) 3.0 (2006):

Faraday
    n 1: the English physicist and chemist who discovered
         electromagnetic induction (1791-1867) [syn: Faraday,
         Michael Faraday]