noun

• A dangerous rock on the Italian coast opposite the whirlpool Charybdis on the coast of Sicily. The passage between Scylla and Charybdis was formerly considered perilous; hence, the saying between Scylla and Charybdis signifies a great peril on either hand.
• (Greek mythology) A personification of said rock as a ravenous monster.
• (Greek mythology) A princess, daughter of King Nisos of Megara, who fell in love with King Minos and betrayed her city to him.
• (astronomy) The main belt asteroid 155 Scylla.