Definition of "supersad"

Lloyd was at training camp in Los Angeles when she heard the news. She called Barbara Klobach and left a voice message, saying it was "supersad news" and adding, "I wasn’t expecting to hear that." She hadn’t known that her former coach had A.L.S.

2015 July 4, Juliet Macur, “Nation's Roars for Carli Lloyd Are Missing the Voice of a Cherished Fan”, in New York Times‎