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

CSNET
       Computer + Science NETwork (USA, network, BITNET)


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

CSNET

   Computers and Science Network, operated by CREN for US
   computer science institutes.  It provides electronic mail
   service via dial-up lines, X.25 and Internet services.