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

Source: Moby Thesaurus II by Grady Ward, 1.0
 

at a loss adj : filled with bewilderment; "at a loss to understand those remarks"; "puzzled that she left without saying goodbye" [syn: at a loss(p), nonplused, nonplussed, puzzled] adv : below cost; "sold the car at a loss"

Source: WordNet (r) 2.0