VMS Help CMS, REMOVE, GENERATION, Qualifiers, /GENERATION[=generation-expression]  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Directs CMS to remove a particular generation of an element
    from one or more classes in the library. The generation must
    be currently existing in the class. If you use a wildcard or a
    list of class names for the class expression, CMS deletes the
    particular generation from each specified class.