Shlomo ben Avraham ibn Aderet (1235 – 1310) was a medieval rabbi, halakhist, and Talmudist. He is widely known as the Rashba (Hebrew: רשב״א), the Hebrew acronym of his title and name: Rabbi Shlomo ben Avraham.
Aderet was born in Barcelona, Crown of Aragon, in 1235. He became a successful banker and leader of Spanish Jewry of his time. As a rabbinical authority his fame was such that he was designated as El Rab d'España ("The Rabbi of Spain"). He served as rabbi of the Main Synagogue of Barcelona for 50 years. He died in 1310.