1. A scripting language produced by IBM in the late 1970s. superseded by REXX. [sC24-5219, "Virtual Machine/system Product EXEC 2 Reference"]. [successor to EXEC 1? With or without a space?] 2. system> An archaic operating system from UNIVAC. By about 1980 it had been replaced by EXEC 8. [Dates? Did EXEC 3 to EXEC 7 exist?] (2000-08-06)