The first half of heliolatry derives from hēlios, the Greek word for "sun." In Greek mythology, Hēlios was the god of the sun, imagined as "driving" the sun as a chariot across the sky. From hēlios we also get the word helium, referring to the very light gas that is used in balloons and airships, and heliocentric, meaning "having or relating to the sun as center," as in "a heliocentric orbit." The suffix -latry, meaning "worship," derives via Late Latin and French from the Greek latreia, and can be found in such words as bardolatry ("worship of Shakespeare") and zoolatry ("animal worship"). A person who worships the sun is called a heliolater.