The Reverend Fr. William J. Fulco, S.J. (born February 24, 1936) is a Jesuit priest and National Endowment for the Humanities Professor of Ancient Mediterranean Studies at Loyola Marymount University in Los Angeles, California in the United States.
Fulco was born in Los Angeles. He entered the Society of Jesus in August 1954 and was ordained a priest in June 1966. He has spent most of his career in education.
He was hired to reconstruct the Aramaic of Jesus for The Passion of the Christ, making him one of the few professional conlangers. His reconstructed Aramaic used in the film incorporated elements of the language of the Book of Daniel, fourth-century Syriac, and Hebrew. Fulco has also worked on such films as "The Nativity Story" and "Constantine."