move back

VERB /muv_bæk/
9 LETTERS · STARTS WITH M

move back is a valid 9-letter word worth 21 points in Scrabble and 25 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
M3O1V4E1B3A1C3K5
3 + 1 + 4 + 1 + 0 + 3 + 1 + 3 + 5 =21 PTS
DOUBLE WORD → 42TRIPLE WORD → 63
MEANING

What does move back mean?