Perplexed means puzzled and unable to see the way through. The frown of somebody genuinely lost.
It is stronger than puzzled and gentler than baffled, and it usually describes an expression as much as a state, so a perplexed look and a perplexed silence are both natural. It takes by. The verb perplex is rare in speech and the adjective is common in writing. The noun perplexity means bewilderment, and a perplexing problem is one that resists every attempt to understand it.
1adjectiveperplexedPuzzled and unable to understand something.
“She looked perplexed by the whole question.”