The two crossword solutions for the term 'Roman God of Sleep' are Somnus (6 letters) and Morpheus (8 letters). Somnus was the Roman god of sleep, while Morpheus was the Greek god of dreams. Both gods were associated with the power to bring sleep and dreams to mortals. Somnus was said to be the son of Nox, the goddess of night, while Morpheus was the son of Hypnos, the god of sleep. Both gods were believed to have the ability to shape-shift into any form they desired.