Synonyms of at a loss

Adjective

1. at a loss(predicate), nonplused, nonplussed, puzzled, perplexed (vs. unperplexed)

usage: filled with bewilderment; "at a loss to understand those remarks"; "puzzled that she left without saying goodbye"

Adverb

1. at a loss

usage: below cost; "sold the car at a loss"