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Synonyms

joist

American  
[joist] / dʒɔɪst /

noun

  1. any of a number of small, parallel beams of timber, steel, reinforced concrete, etc., for supporting floors, ceilings, or the like.


verb (used with object)

  • joists,
    present (3rd person singular)
  • joisted,
    past participle,  past
  • joisting
    present participle
  1. to furnish with or fix on joists.

joist British  
/ dʒɔɪst /

noun

  1. a beam made of timber, steel, or reinforced concrete, used in the construction of floors, roofs, etc See also rolled-steel joist

"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

verb

  1. (tr) to construct (a floor, roof, etc) with joists

"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

Other Word Forms

Derived Forms

Inflected Forms

Participles

Conjugated Forms

Present

Past

Future

Etymology

Origin of joist

1325–75; Middle English giste < Old French < Latin *jacitum support, noun use of neuter of Latin jacitus (past participle of jacēre to lie), equivalent to jaci- variant stem + -tus past participle suffix

Explanation

A joist is a support that strengthens floors and ceilings in a house. Joists run horizontally, connecting with the studs in walls to give buildings a solid frame. You can't see the joists in a finished house or building, because they're inside the foundation, walls, or ceiling. Joists are usually made of wood, although they can also be concrete or steel, materials strong enough to provide support. Ceiling joists often connect to beams, which tend to be larger and run perpendicular to joists. Joist comes from the Old French word giste, "beam supporting a bridge," from the Latin iacere, "to rest."

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Vocabulary lists containing joist

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

You don’t want the nails to rust years from now and have the joist fail.

From Seattle Times ● Dec. 11, 2023

The home was badly damaged and every roof joist was left burnt by the fire.

From BBC ● Dec. 20, 2022

Put it in a ceiling joist or reinforced that particular area.

From Salon ● Jul. 10, 2022

This same corrosion can be happening with any of the joist hangers and other structural framing connectors.

From Washington Post ● May 24, 2022

He sized up a plank and laid it against what was left of a joist.

From "The Teacher’s Funeral" by Richard Peck

The often-expansive data-center buildings typically have steel frames made up of wall pillars, roof joists and roof sheeting.

From The Wall Street Journal ● Jun. 29, 2026

Machines cut lumber and route utility pathways; nail guns connect joists, studs and weather wrap; other machines blow in insulation, all guided by a digital model.

From Los Angeles Times ● May 9, 2025

Inside Mr. Zulkibli’s 50-foot-high birdhouse, wooden joists crisscross the ceilings, creating places for birds to make their nests.

From New York Times ● Apr. 2, 2024

The sophisticated wood artifacts from Schöningen join finds from just a scattering of other sites, such as 476,000-year-old wood joists from Zambia published last year and spears and other tools found elsewhere in Europe.

From Science Magazine ● Mar. 31, 2024

The sound of joists snapping and rivets popping echoed through the stairwell.

From "Salt to the Sea" by Ruta Sepetys

The tunnel vault and the joisted ceiling were equally well suited to the long galleries of Assyrian palaces.

From A History of Art in Chaldæa & Assyria, v. 1 by Sir Walter Armstrong

She is a tank ribbed, joisted, stayed, but she is no greater mystery than a tank. 

From Notes on Life and Letters by Joseph Conrad

In the windows sat stately dames and beautiful maidens, featly adorned, and gazed down at the joisting of the warriors, till that the king himself began to tilt with his kinsmen.

From The Fall of the Niebelungs by Margaret Armour

"I look to see some handsome joisting," said Don Pedro, who rode with the King of Majorca upon the right of the prince, while Chandos was on the left.

From The White Company by Sir Arthur Conan Doyle

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