WordNet (r) 3.0 (2006):

MEK
    n 1: a terrorist organization formed in the 1960s by children of
         Iranian merchants; sought to counter the Shah of Iran's
         pro-western policies of modernization and opposition to
         communism; following a philosophy that mixes Marxism and
         Islam it now attacks the Islamic fundamentalists who
         deposed the Shah [syn: Mujahidin-e Khalq Organization,
         MKO, MEK, People's Mujahidin of Iran]