To recognize and remember who someone is. They showed me a picture of a suspect and asked if I knew who it was, but I couldn't place her. A: "Do you remember my friend Tom?" B: "I know the name, but I can't place him."
See also: place
to recall someone's name; to recall the details about a person that would help you identify the person. I am sorry, I can't seem to place you. Could you tell me your name again? I can't place her. Did I meet her once before?