Related Clues:

• Cul-de- --
• Hole in your head
• It may be congested
• Egg container, sometimes
• Type of cavity
• Wisconsin tribe
• Amniotic ___
• Old U.S.A.F. org.
• See 128-Across
• Air-filled skull cavity
• Hole in the head?
• Biological cavity
• Cold place?
• It might be filled with ink
• Spider's pouch