stumble across(redirected from stumble on someone or something)
stumble across someone or somethingand stumble (up)on someone or something; stumble into someone or something
to find someone or something, usually by accident. I stumbled across an interesting book yesterday when I was shopping. Guess who I stumbled into at the library yesterday? I got lucky and stumbled on the right answer.
Also, stumble on. Find by chance, discover or meet with unexpectedly. For example, When we were hiking up the mountain we stumbled across a few abandoned shepherd's huts , or At the flea market Alfred stumbled on a quite valuable old lithograph. This idiom uses stumble in the sense of "accidentally trip." [Mid-1500s]
To come upon someone or something accidentally or unexpectedly: I had given up finding my keys when I stumbled across them lying under the dresser. On my way to work this morning, I stumbled across an old friend I hadn't seen in years.