Related Clues:

• Drop to the bottom
• Inundate
• Kitchen basin
• Invest, so to speak
• Be more dense than water, say
• Where dirty dishes pile up
• Lose altitude
• Make a putt
• Become clear, with "in"
• Founder
• Slope downward
• Be covered with, with 'in'
• Set, as the sun
• Succumb to quicksand
• Hole, as a putt