WordNet (r) 3.0 (2006):

give in
    v 1: yield to another's wish or opinion; "The government bowed
         to the military pressure" [syn: submit, bow, defer,
         accede, give in]
    2: consent reluctantly [syn: yield, give in, succumb,
       knuckle under, buckle under]

Moby Thesaurus II by Grady Ward, 1.0:

35 Moby Thesaurus words for "give in":
   back down, bow to, break off combat, cave in, cease resistance,
   circulate, come across with, deliver, deliver over, distribute,
   fork over, forward, give ground, give out, give over, give up,
   give way, hand, hand in, hand it to, hand out, hand over,
   lose face, pass, pass out, pass over, quit the field, reach,
   render, resign, surrender, transfer, turn over, yield,
   yield the palm