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bread-and-butter model

American  

noun

  1. Naval Architecture. a wooden hull model carved from a number of horizontal planks glued together to represent the outlines of the various decks.

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.