WordNet (r) 3.0 (2006):

come back
    v 1: be restored; "Her old vigor returned" [syn: come back,
         return]
    2: go back to something earlier; "This harks back to a previous
       remark of his" [syn: hark back, return, come back,
       recall]
    3: even the score, in sports
    4: answer back [syn: retort, come back, repay, return,
       riposte, rejoin]

Moby Thesaurus II by Grady Ward, 1.0:

48 Moby Thesaurus words for "come back":
   acknowledge, answer, answer back, bounce back, come around,
   come back at, come home, come round, come to, come up smiling,
   double, double back, echo, flash back, get about, get over,
   get well, give acknowledgment, give answer, go back, go home,
   make a comeback, pull round, pull through, put back, rally, react,
   recover, recur, reecho, rejoin, reply, respond, retort, return,
   return answer, return for answer, return to mind, reverberate,
   revive, riposte, say, say in reply, shoot back, survive, talk back,
   turn back, weather the storm