Scuttle. Small opening - in a deck, side of a ship, or compartment - that can be closed as required. Literally means a 'shutter'.
Scuttle Butt. Covered cask, having lid in head, in which fresh water for current use was formerly carried.
Scuttling. Deliberately making, or uncovering, any opening in a vessel so that sea can enter. Sometimes done to allow water to enter a stranded ship to prevent her bumping on the ground.
Scylla. One of the whirlpools (garofali) in Straits of Messina, named after a fabulous monster. Sea. Large expanse of water forming part of an ocean, or connected with it. 2. Waves or swell. 3. The movement and direction of waves. 4. Large inland lake.