Nafissatou "Nafi" Thiam (French pronunciation: ​[tʃam]; born 19 August 1994) is a Belgian athlete specializing in multi-event competition. Thiam is a two-time Olympic gold medalist, winning the heptathlon event at the 2016 and 2020 Summer Olympics. She is the only Belgian athlete, male or female, to successfully defend an Olympic title and only the second woman after Jackie Joyner-Kersee to win back-to-back Olympic titles in the event. In May 2017, at the Hypo-Meeting in Götzis, Austria, she became only the fourth woman to break the heptathlon 7000 point-barrier.