move
c-from c-to ucount -- core "move"
erase
addr len -- core-ext "erase"
While the previous words work on address units, the rest works on characters.
cmove
c-from c-to u -- string "cmove"
cmove>
c-from c-to u -- string "c-move-up"
fill
c-addr u c -- core "fill"
blank
addr len -- string "blank"