U-boat

Calque of German U-Boot.

 

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U-boat

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U-boat (plural U-boats)

1. (military, nautical, historical) Any German submarine of the First or Second World War, or any Austro-Hungarian submarine of the First World War.
2. (shipping) A narrow utility cart with tall handles on both ends that is used to carry loads of retail products to be sold, so named because its shape is roughly that of a capital U.
3. (rail transport, slang) Nickname given to the General Electric Universal Series diesel-electric locomotives.

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