any organization that develops and approves standards using various methods to establish consensus among its participants. Such organizations may be: accredited, such as ANSI -accredited IEEE; international treaty based, such as the ITU- T; private sector based, such as ISO/IEC; an international consortium, such as OASIS or IETF; or a government agency.
Sources:
NISTIR 8074 Vol. 2
under Standards Developing Organization