The Collaborative International Dictionary of English v.0.48:

Supply \Sup*ply"\, v. t. [imp. & p. p. Supplied; p. pr. & vb.
   n. Supplying.] [For older supploy, F. suppl['e]er, OF. also
   supployer, (assumed) LL. suppletare, from L. supplere,
   suppletum; sub under + plere to fill, akin to plenus full.
   See Plenty.]
   1. To fill up, or keep full; to furnish with what is wanted;
      to afford, or furnish with, a sufficiency; as, rivers are
      supplied by smaller streams; an aqueduct supplies an
      artificial lake; -- often followed by with before the
      thing furnished; as, to supply a furnace with fuel; to
      supply soldiers with ammunition.
      [1913 Webster]

   2. To serve instead of; to take the place of.
      [1913 Webster]

            Burning ships the banished sun supply. --Waller.
      [1913 Webster]

            The sun was set, and Vesper, to supply
            His absent beams, had lighted up the sky. --Dryden.
      [1913 Webster]

   3. To fill temporarily; to serve as substitute for another
      in, as a vacant place or office; to occupy; to have
      possession of; as, to supply a pulpit.
      [1913 Webster]

   4. To give; to bring or furnish; to provide; as, to supply
      money for the war. --Prior.
      [1913 Webster]

   Syn: To furnish; provide; administer; minister; contribute;
        yield; accommodate.
        [1913 Webster]

WordNet (r) 3.0 (2006):

supplying
    n 1: the activity of supplying or providing something [syn:
         provision, supply, supplying]