/euh sas"in/ , n.
1. a murderer, esp. one who kills a politically prominent person for fanatical or monetary reasons.
2. ( cap. ) one of an order of Muslim fanatics, active in Persia and Syria from about 1090 to 1272, whose chief object was to assassinate Crusaders.
[ 1525-35; assassini (pl.) hashshashin eaters of HASHISH ]