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firestop

American  
[fahyuhr-stop] / ˈfaɪərˌstɒp /

noun

  1. any object built into a building frame to block a concealed hollow space through which a fire might pass from one part of the building to another.

Etymology

Origin of firestop

An Americanism dating back to 1895–1900; fire + stop

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.