joist

Etymology

It is inherited from Middle English giste, also gyste and later joiste,^[2][3] borrowed from Old French giste (“a beam supporting a bridge”) (modern French gîte),^{[3][4][5][6][7]} the noun use of a past participle of gesir (“to lie”),^[4][8][9] from Latin iaceō (“to lie, rest”).^[3][4][8] Etymonline, Barnhart and the American Heritage Dictionary take the French noun from the feminine participle, Merriam-Webster Unabridged, Ayto and Hoad from the neuter, Vulgar Latin *jacitum,^{[4][8][9][10][7][5]} and Klein from a feminine *jacita (“a lying place”).^[11] The Latin verb is related to iaciō (“to throw”),^[4][8] from Proto-Indo-European *ye- (“to throw, impel”).^[4] The Anglo-Norman noun, recorded from the 1190s, meant a lodging or resting place as well as a joist or beam.^[12] The change of the vowel to “oi”, also seen in hoist and foist, is older than the alternation in boil and bile, and has not been explained.^[3][8]

Earliest recorded meaning

One of the timbers carrying a floor: before 1325, the plural gistes glossing a French word for floor beams in Bibbesworth's treatise.^[2][8] The OED's first quotation is from 1379.^[3]

Semantic evolution

Ayto explains a joist as a beam on which the floorboards "lie".^[7] Weekley compares the railway sleeper for the same idea.^[13] In Middle English the word also meant a stand for casks of ale, and in Cornwall any beam or timber;^[2] a giste tre was a girder that carried the joists.^[2][13] The general sense "a beam, plank or deal" lasted from 1487 to 1661.^[3] The spelling began to change to joist from the 15th century.^[7][2] Johnson (1755) defined it as the secondary beam of a floor and traced it to French joindre.^[14] A short-lived 19th-century sense, a mass of mineral in its bed, followed modern French gîte.^[3] The verb, to furnish with joists, is recorded from 1439,^[8] the OED's first record being from before 1615.^[3]

Timeline

• before 1325 – gistes, the timbers supporting a floor.^[2][8] The OED's first quotation is from 1379.^[3]
• 1439 – verb, to furnish with joists.^[8] The OED's first record of the verb is from before 1615.^[3]
• 1487 – a beam, plank or deal (obsolete by 1661).^[3]
• 1829 – a mass of mineral in its natural bed (obsolete).^[3]
• 1839 – verb, to fix on joists.^[3]

Meanings

Noun

1. One of the parallel beams of timber, steel or reinforced concrete that hold up the boards of a floor or the laths of a ceiling: The old floor sagged where a joist had rotted.^[15][10][3]
2. (obsolete, 1487–1661) Any beam, plank or deal.^[3][2]

Verb

1. To build or furnish a floor or roof with joists.^[15][10][3]

Word family

• joistless

Related words

• gist
• agist
• adjacent
• jet

Usage notes

Merriam-Webster Unabridged records a dialect pronunciation rhyming with iced,^[10] and Skeat notes that it was sometimes said jist;^[16] Wright's dialect dictionary lists forms such as jist, jeest and joice.^[17] A separate dialect verb joist, to take in cattle to graze for a fee, is a variant of agist, recorded from 1601 to 1851.^[3][17]

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g Kurath, Hans; Kuhn, Sherman M.; Lewis, Robert E., eds. (1952–2001), Middle English Dictionary, Ann Arbor: University of Michigan Press; online edition ed. Frances McSparran et al. (2000–2018)
3. ^ a b c d e f g h i j k l m n o p q Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
4. ^ a b c d e f Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
5. ^ a b Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
6. ^ Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
7. ^ a b c d Ayto, John (2005), Word Origins: The Secret Histories of English Words from A to Z, 2nd ed., London: A & C Black
8. ^ a b c d e f g h i Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
9. ^ a b The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
10. ^ a b c d Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
11. ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
12. ^ Anglo-Norman Dictionary (AND2), Aberystwyth University, anglo-norman.net (2nd ed., 2005–)
13. ^ a b Weekley, Ernest (1921), An Etymological Dictionary of Modern English, London: John Murray
14. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
15. ^ a b Collins English Dictionary (2023), Glasgow: HarperCollins
16. ^ Skeat, Walter W. (1911), A Concise Etymological Dictionary of the English Language, new ed., Oxford: Clarendon Press
17. ^ a b Wright, Joseph, ed. (1898–1905), The English Dialect Dictionary, 6 vols., Oxford: Henry Frowde; via EDD Online 4.0, University of Innsbruck (CC BY 4.0)