Source : Webster's Revised Unabridged Dictionary (1913)

Signatory \Sig"na*to*ry\, a. [L. signatorius.]
   1. Relating to a seal; used in sealing. [Obs.] --Bailey.

   2. Signing; joining or sharing in a signature; as, signatory
      powers.

Signatory \Sig"na*to*ry\, n.; pl. {-ries}.
   A signer; one who signs or subscribes; as, a conference of
   signatories.

Source : WordNet®

signatory
     n : someone who signs and is bound by a document [syn: {signer}]