The Collaborative International Dictionary of English v.0.48:

Ansa \An"sa\ ([a^]n"s[.a]), n.; pl. Ans[ae] ([a^]n"s[=ae]).
   [L., a handle.] (Astron.)
   A name given to either of the projecting ends of Saturn's
   ring.
   [1913 Webster]

V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

ANSA
       Advanced Networked Systems Architecture (ISA)


The Free On-line Dictionary of Computing (30 December 2018):

Advanced Network Systems Architecture
ANSA

    (ANSA) A "software bus" based on a model for
   distributed systems developed as an ESPRIT project.

   (http://ansa.co.uk/).

   (1996-04-01)