Alone-time with a dear friend. Something like the Renaissance, but referred to as a refreshing of an old friendship between two people. You have one of these with a friend when you have not hung out with them in a while and you miss them in your life. The word originated from "Phoebe" on the sitcom "Friends" when she had one with Joe!
A get-together, a renewing of friendship, friend time, Frienaissance.