Related Clues:

• Two-thirds of Earth
• Gulp from a bottle
• Sound source
• It makes a sound
• It has a floor but no ceiling
• Mermaid home
• Briny expanse
• Rivers' destination
• Big swallow
• Imbibe
• Atlantis cover, supposedly
• Crossing medium
• It has arms and waves
• Mariner's milieu
• Most of the Earth's surface