faulty

Etymology

It is inherited from Middle English fauti,^[2] formed from English fault + -y.^[3][4][5][6] Etymonline, Merriam-Webster and the Shorter Oxford take the noun as its base, the OED the verb,^[3][4][5][7] and the OED and the Shorter Oxford think it was perhaps or partly modelled on French fautif,^[7][5] from which Johnson derived it.^[8] The noun fault is faute, from Old French faute, from Vulgar Latin *fallita (“a shortcoming, falling”), from Latin fallō (“to deceive, disappoint”); the -l- was put back in the 16th century in imitation of Latin.^[3]

Earliest recorded meaning

Of immaterial things, containing faults, defective, and of people, guilty of a fault: both in 1380, in Wyclif's works.^[7] Of material things it is recorded from 1434.^[7]

Semantic evolution

In Middle English the adjective also meant lacking or wanting, needy, and out of repair; a London letter book of 1441 calls short-weighted bread fawty.^[2] The sense "guilty, to blame" is now obsolete or long rare;^[7][5] Collins labels it archaic.^[9] Johnson (1755) still listed it first, before "wrong, erroneous" and "defective, not fit for the use intended".^[8] The sense "having failings", of people and their character, appears in 1574.^[7][5] In English dialects faulty meant rotten or decayed, said of potatoes in Cheshire and Wiltshire, and in Warwickshire and Somerset fault-finding or scolding.^[10]

Timeline

• 1380 – of immaterial things, defective; of people, guilty of a fault.^[7]
• 1434 – of material things, defective.^[7]
• 1441 – of bread, short of weight.^[2]
• 1548 – of the nature of a fault, censurable.^[7]
• 1574 – of people, having failings.^[7]

Meanings

Adjective

1. Not working properly or made badly; defective: a faulty smoke alarm.^[9][4][7]
2. Containing mistakes; unsound: The conclusion rests on faulty data.^[4][7]
3. Of people, having failings or apt to do wrong.^[4][7][5]
4. Of the nature of a fault; deserving blame.^[7][5]
5. (archaic) Guilty of a fault; to blame.^[9][7][5]

Word family

• faultily
• faultiness
• nonfaulty
• unfaulty

Related words

• fault
• fail
• false

References

1. ^ a b Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c 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 Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b c d e Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
5. ^ a b c d e f g h Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
6. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
7. ^ a b c d e f g h i j k l m n o Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
8. ^ a b Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
9. ^ a b c Collins English Dictionary (2023), Glasgow: HarperCollins
10. ^ 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)