From Longman Dictionary of Contemporary EnglishDe Klerk, F.W.F.W. De KlerkDe Klerk, F.W. /də ˈklɜːk $ -ˈklɜːrk/(1936–) the president of South Africa from 1989 to 1994. He made many political changes and finally ended the system of apartheid. In 1990 he allowed the anc to become a legalorganization again, and let Nelson mandela out of prison. He and Mandela won the Nobel PeacePrize in 1993.