Which celestial body is named after a Roman god or goddess? Ceres Haumea Titania Ariel

The answer is Ceres, named after the Roman goddess of agriculture (the Greek equivalent of Ceres is Demeter).

Haumea was named after the Hawaiian goddess of childbirth, Titania was named after a character in Shakespeare's "A Midsummer Night's Dream," and Ariel was named after two characters in literature.