sponson

American  

[spon-suhn] / ˈspɒn sən /

noun

1. a structure projecting from the side or main deck of a vessel to support a gun or the outer edge of a paddle box.

2. a buoyant appendage at the gunwale of a canoe to resist capsizing.

3. Aeronautics. a protuberance at the side of a flying-boat hull, designed to increase lateral stability in the water.

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sponson British  

/ ˈspɒnsən /

noun

1. navy an outboard support for a gun enabling it to fire fore and aft

2. a semicircular gun turret on the side of a tank

3. a float or flotation chamber along the gunwale of a boat or ship

4. a structural projection from the side of a paddle steamer for supporting a paddle wheel

5. a structural unit attached to a helicopter fuselage by fixed struts, housing the main landing gear and inflatable flotation bags

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Etymology

Origin of sponson

First recorded in 1825–35; variant of expansion

Example Sentences

In an online post in November 2007, he said there was "no way I want to own a sponson… nor do I seek to own any part of K7".

From BBC • Mar. 7, 2024

On the right sponson, a large portrait of Howard Lincoln, and on the left, Chuck Armstrong.

From Seattle Times • Aug. 13, 2010

Each sponson sports a modified-V design with hard chines that reduce spray and let the boat come to plane quickly and run level.

From Time Magazine Archive

"Ah-h-h!" goes on Mr. Mason, foldin' his hands over his forward sponson and rollin' his eyes sentimental.

From The House of Torchy by Brown, Arthur William

There he lay, along one side of the tank between the engine and the sponson.

From Life in a Tank by Haigh, Richard