move

MOVE  -  copy the current message into another mail file, and delete...

Usage:  MOVE [/type] filename
  Unless specified, type is "/mbox".

The MOVE command copies the message to another mail file, and marks it as 
  deleted in the current mail file (compare to COPY).  

If the mail file named exists, MOVE adds a copy of the message to the end 
  of the file.  If the mail file does not exist, MOVE creates it, unless
  the variable auto-create-files is set to NO.  If a directory is not 
  specified with the filename, MOVE assumes the MAIL-DIRECTORY, which by 
  default is your home directory. 

If a type is not specified, /mbox is used for new files and the existing
  type is retained for existing files.  Use the type /mbox unless you also 
  use another mail system that needs another format.  /babyl and /mtxt 
  are the other types. 
  
Example:               
    Read>move oldmail                #to a mail file called oldmail

For more help type "help" and one of these topics:
  copy   headers   filing
  set auto-create-files   set default-mail-type   set mail-directory