from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A hole or opening through which gas or air may pass.
- n. An opening in the frozen surface of a body of water.
- n. See air pocket.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. a hole in any surface that allows air or other gases to pass, especially an opening in the surface of a frozen lake etc
- n. an air pocket
- n. the blowhole of a whale
from the GNU version of the Collaborative International Dictionary of English
- A hole to admit or discharge air; specifically, a spot in the ice not frozen over.
- A fault in a casting, produced by a bubble of air; a blowhole.
- 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.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a local region of low pressure or descending air that causes a plane to lose height suddenly
- n. a hole that allows the passage of air
Sorry, no etymologies found.