A person who is your friend, but only because he is one of your friend's friends. It doesn't really matter how much you like him, or how often you converse, he is still your friend by association. But he can only be a friend by association if you have met him, (and not just heard about him) and talked to him.
Erik is Chris's friend. Josh is Erik's friend. Erik introduced him to Chris. Chris greeted him. Josh is now Chris's friend by association, and vice versa.
by Christophart August 22, 2010