Meaning of who in English
Interrogative pronoun
1. what or which person or people
Who is she?
1. ⦅in restrictive use⦆ of the kind that; that
Edison was an American inventor and businessman who has been described as America's greatest inventor.
2. ⦅in non-restrictive use⦆ and/but he, she, or they, used with comma
I lived with Mary, who taught me English.