go under
     v 1: go under, "the raft sank and its occupants drowned" syn: sink,
           settle, go down ant: float
     2: disappear beyond the horizon; "the sun sets early these
        days" syn: set, go down ant: rise
     3: be called; go by a certain name; "she goes by her maiden
        name again" syn: go by
see also:
sink settle go down float set rise 
go by 

44 moby thesaurus words for "go under":
   be ruined, become insolvent, bite the dust, bow, break, bust,
   collapse, crash, fail, fall, fold, fold up, founder, go bankrupt,
   go broke, go down, go downhill, go into receivership, go to glory,
   go to hell, go to perdition, go to pot, go to ruin, go to shivers,
   go to smash, go to smithereens, go up, go wrong, have enough,
   lick the dust, lose, lose out, lose the day, say uncle, shut down,
   sink, slip, submerge, submerse, submit, succumb, surrender,
   take the count, tumble