airhole

noun3

1. •
   A hole provided for ventilation or breathing.

   • For if they touch one another, and so do not leave airholes and admit draughts of air to blow between them, they get heated and soon begin to rot. — 1914
2. •
   A hole in ice through which air escapes.

   • "Even if it is hard enough, there may be airholes around." — 1914
3. •
   An air pocket.