Bon Mots

This word baffles me. When I hear nonplussed, I picture Sherlock Holmes with his arms crossed, a disinterested stare in his eyes, while Holmes stands by, awaiting a clever deduction. Then I think, no, that’s not right. And I look up the definition, only to find I did have it right. To be nonplussed is to be unfazed, disinterested. But then I read further, and find the word also means bewildered, unsure of how to respond. I somehow doubt that Sherlock spent a millisecond being unsure of how to respond. So does this word mean baffled or does it mean disinterested? I’m feeling nonplussed by this word. It’s an enigma to me. Hmm, now there’s a bon mot.