Abbreviation of Enhanced Expanded Memory Specification, an enhanced version of the original EMS, which enables DOS applications to use more than 1MB (megabyte) of memory. EEMS was developed by AST, Quadram, and Ashton-Tate to improve the performance of the original version of EMS. Subsequently, Lotus, Intel, and Microsoft developed the LIM 4.0 version of EMS, which supports both the original EMS and EEMS.