Dia-

from The Collaborative International Dictionary of English v.0.48

Dia- \Di"a-\, Di- \Di-\ . [Gr. dia` through; orig., dividing
   into two parts; akin to ? two. See {Two}, and cf. 1st {Di-}.]
   A prefix denoting through; also, between, apart, asunder,
   across. Before a vowel dia- becomes {di-}; as, diactinic;
   dielectric, etc.
   [1913 Webster]

from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)

DIA
       Deutsche Informatik Akademie (org.)

from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)

DIA
       Document Interchange Architecture (IBM, CCS)