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'tween deck

American  

noun

Nautical.

  1. any space between two continuous decks in the hull of a vessel, as between a shelter deck and a freeboard deck.

'tween deck British  

noun

  1. nautical a space between two continuous decks of a vessel

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of 'tween deck

First recorded in 1810–20

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.