You're right, don't know what it refers to though. Probably some library or internal which acad uses. Can't seem to figure any correlation:Command: ACADVER
ACADVER = "19.0s (LMS Tech)" (read only)
Command: (ver)
"Visual LISP 2013 (en)"
Command: _VERNUM
_VERNUM = "G.55.0.0 (UNICODE)" (read only)