microraion UK /ˌmaɪkɹəʊˌɹaɪˈjɒn/US /ˌmaɪkɹoʊˌɹaɪˈjɔn/ noun1 •A residential complex in a current or former communist country, chiefly one which was previously part of the Soviet Union; a microdistrict.Raions in turn are divided into mikroraions, analogous to neighborhoods. […] Zheks and mikroraions emphasize citizen involvement on a cooperative, voluntary basis. — 1985 formsmicroraions · microraiony