D defs.my
Entry 3 senses Webster, 1913

Air hole

/(âr" hōl`)/ · Air· hole · IPA
01 A hole to admit or discharge air; specifically, a spot in the ice not frozen over.
  1. 1.
    A hole to admit or discharge air; specifically, a spot in the ice not frozen over.
  2. 2.
    A fault in a casting, produced by a bubble of air; a blowhole.(Founding)
  3. 3.
    A local region in the atmosphere having a downward movement and offering less than normal support for the sustaining surfaces of a flying machine, causing an airplane to drop suddenly. Same as air pocket.(Aëronautics) Also: air pocket