Library /sys$common/syshlp/dce$uaf_help.hlb DEFINE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Associates equivalence names with a logical name. If you specify
 an existing logical name, the new equivalence names replace the
 existing equivalence name. The DEFINE command can be used with
 the /KEY qualifier:

 o  The /KEY qualifier associates an equivalence string and a set
    of attributes with a key on the terminal keyboard (see /KEY).

    Format:

    DEFINE  logical-name equivalence-name[,...]

  Additional Information (explode) :

• /KEY