\ ˈjȯist \

Definition of joist

: any of the small timbers or metal beams ranged parallel from wall to wall in a structure to support a floor or ceiling

Illustration of joist

Illustration of joist

J joist

Examples of joist in a Sentence

Recent Examples on the Web

Subfloor The wood flooring that's installed over the joists to provide stability. Brett Martin, House Beautiful, "See The Definitions Of Common Renovation Terms," 26 Dec. 2018 If the insulation in your attic doesn't reach the top of the floor joists, there's not enough to trap heat. The Good Housekeeping Institute, Good Housekeeping, "How to Draft-Proof Your Home for a Lower Heating Bill," 20 Nov. 2018 Cut all the 2 x 6 floor joists to length and set them between the two band joists and on top of the mudsills. Joseph Truini, Popular Mechanics, "How to Build a Shed, Colonial-Style," 19 Apr. 2017 In one of them, Christian Bandler, the construction manager for the restaurant’s renovation, stepped carefully across a lattice of thick, wooden joists and beams. Corey Kilgannon, New York Times, "The Elite Are Locked Out, While ‘21’ Dries Out," 31 Jan. 2018 This is why floor joists are always vertically oriented. 13. Popular Mechanics Editors, Popular Mechanics, "15 Things My Father Taught Me," 17 June 2016 The entrance to this unit is at the side of the building, up a flight of stairs created from salvaged floor joists. Julie Lasky, New York Times, "$2.3 Million Homes in New York, Florida and Colorado," 11 Apr. 2018 Next, form each front and rear band joist by nailing a 2 x 6 to a 2 x 8 mudsill. Joseph Truini, Popular Mechanics, "How to Build a Shed, Colonial-Style," 19 Apr. 2017 The kitchen, which had to be gutted because powderpost beetles had eaten the rafters and joists, feels simultaneously fresh and quaint. Marni Elyse Katz,, "Once a sea captain’s cottage, this Cotuit fixer-upper brings on the charm," 15 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'joist.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of joist

15th century, in the meaning defined above

History and Etymology for joist

Middle English giste, joiste, from Anglo-French giste, from Vulgar Latin *jacitum, from Latin jacēre to lie — more at adjacent

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Last Updated

29 Jan 2019

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Time Traveler for joist

The first known use of joist was in the 15th century

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More Definitions for joist



English Language Learners Definition of joist

: a strong, heavy board that supports a floor or ceiling


\ ˈjȯist \

Kids Definition of joist

: any of the small timbers or metal beams laid crosswise in a building to support a floor or ceiling

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More from Merriam-Webster on joist

Rhyming Dictionary: Words that rhyme with joist

Spanish Central: Translation of joist

Nglish: Translation of joist for Spanish Speakers Encyclopedia article about joist

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