The term 'CAESAR'S BEAR' is a reference to the constellation URSA Major, which is also known as the Great Bear. The Latin name for this constellation is URSA Major, which can be abbreviated to URSA, a four-letter word that is often used in crossword puzzles. URSA Major is one of the most recognizable constellations in the night sky and is associated with the mythological figure of Callisto, who was transformed into a bear by Zeus.