Antisemitism as a noun is (narrower sense) prejudice, discrimination, hostility or political or religious opposition directed against ethnic or religious jews or against judaism; antijudaism; judeophobia. while Anti-Semitism as a noun is prejudice, discrimination or hostility directed against jews.
Part of speech: noun
Definition: (narrower sense) Prejudice, discrimination, hostility or political or religious opposition directed against ethnic or religious Jews or against Judaism; antijudaism; judeophobia.
Part of speech: noun
Definition: Prejudice, discrimination or hostility directed against Jews.
We hope you now know whether to use Antisemitism or Anti-Semitism in your sentence.