The DICT Development Group

  31 Moby Thesaurus words for "at a loss":
     addled, at a nonplus, at a stand, at a standstill, at an impasse,
     baffled, bamboozled, beat, bewildered, buffaloed, confounded,
     dazed, floored, fuddled, in a dilemma, in suspense, in the red,
     licked, muddled, mystified, nonplussed, on tenterhooks, out,
     out of pocket, perplexed, puzzled, stuck, stumped, thrown,
     to the bad, unprofitably