Commercial Instruction Set
From Computer History Wiki
A Commercial Instruction Set (sometimes named an 'Extended Instruction Set') was an option in a number of early computers to support more efficient processing of business applications; it generally included binary-coded decimal support.
In DEC's VAX line of computers, the early models included hardware support for the VAX architecture's Commercial Instruction Set, but this was dropped in later models; any such instructions found in the object code as a program ran were emulated.