to assume a facial expression
indicating pleasure, favor, or amusement,
characterized by an upturning of the corners of the mouth.
Here is an excerpt of an actual telephone
conversation I had last week with a stranger:
S: Yes. I can help you--but first, who is your hero?
Me: Um. Well...It's Kellie.
S: Can you spell that?
S: Yes. That is correct.
At least I got it right.