air hole

American  

noun

1. an opening to admit or discharge air.

2. a natural opening in the frozen surface of a river or pond.

3. air pocket.

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air hole British  

noun

1. a hole that allows the passage of air, esp for ventilation

2. a section of open water in a frozen surface

3. a less common name for air pocket

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Etymology

Origin of air hole

First recorded in 1760–70

Example Sentences

Then I cracked open one eye and found a tiny air hole at the top of my hat.

From Washington Post • Jan. 15, 2015

Its oxygen became so depleted that by the time their rescuers managed to bore a fresh air hole for them, they had begun to vomit.

From Time Magazine Archive

The old cap had a rubber seal that, because it tended to swell up and cover the cap's air hole, could have caused the gas tank to collapse.

From Time Magazine Archive

It was the air hole for a muskrat den.

From "Where the Red Fern Grows" by Wilson Rawls

At another place, under a tree in the village, he saw a blacksmith's anvil fixed in a block; the forge was of masonry, having an air hole, but the bellows was wanting.

From Account of a Voyage of Discovery to the West Coast of Corea, and the Great Loo-Choo Island by Hall, Basil