Castor and Pollux are TWIN brothers in Greek mythology, often referred to as the Dioscuri. They were the sons of Zeus and Leda, and were known for their bravery and loyalty. Castor was a skilled horseman and Pollux was an expert boxer. In astronomy, they are represented by the stars Alpha and Beta Geminorum, also known as Castor and Pollux. The crossword solutions for the term Castor or Pollux are 'TWIN' (4 letters) and 'STAR' (4 letters). This is because Castor and Pollux are twins, and they are represented by two stars in the night sky.