The definition of signatory is being bound by the signing of a document.(adjective)
An example of signatory is the person who signed a rental agreement and is responsible for the rent.
Signatory is defined as any of the people that signed a document.(noun)
An example of a signatory is a person who signed a contract.
See signatory in Webster's New World College Dictionary
Origin: L signatorius, of sealing, of a signer < signator, one who seals or signs < signare, to set a seal upon, sign: see sign
noun pl. signatories
See signatory in American Heritage Dictionary 4
Origin: Latin signātōrius
Origin: , from signātus
Origin: , past participle of signāre, to mark
Origin: , from signum, sign; see sign.
Learn more about signatory