anti-Semitism (n.) Look up anti-Semitism at Dictionary.com
also antisemitism, 1881, from German Antisemitismus, first used by Wilhelm Marr (1819-1904) German radical, nationalist and race-agitator, who founded the Antisemiten-Liga in 1879; see anti- + Semite.

Not etymologically restricted to anti-Jewish theories, actions, or policies, but almost always used in this sense. Those who object to the inaccuracy of the term might try Hermann Adler's Judaeophobia (1882). Anti-Semitic (also antisemitic) and anti-Semite (also antisemite) also are from 1881, like anti-Semitism they appear first in English in an article in the "Athenaeum" of Sept. 31, in reference to German literature.