Mossad Syllabification: (Mos·sad)Pronunciation: /mäˈsäd, mə-/Definition of Mossad 1the Supreme Institution for Intelligence and Special Assignments, the principal secret intelligence service of the state of Israel, founded in 1951. 2the Institution for the Second Immigration, an earlier organization formed in 1938 for the purpose of bringing Jews from Europe to Palestine. Origin:from Hebrew mōsāḏ 'institution'Mossad in other Oxford dictionaries Definition of Mossad in the British & World English dictionary