Chabad n 1: a large missionary Hasidic movement known for their hospitality, technological expertise, optimism and emphasis on religious study [syn: {Lubavitch}, {Lubavitch movement}, {Chabad-Lubavitch}] 2: a form of Hasidism practiced by Lithuanian and Russian Jews under communist rule; the beliefs and practices of the Lubavitch movement [syn: {Chabad Hasidism}]