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deductible

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Etymology and origin of the English word deductible

Confidence
Established
Formation
Derivation
First attested
1856 Elizabeth Barrett Browning, Aurora Leigh
Ultimate origin
Latin dūcō

Pronunciation

  • UK: [dɪˈdʌktəbəɫ], [dɪˈdʊktəbəɫ][1]

Etymology

It is formed from English deduct + -ible,[2][3][4] or, as the OED puts it, from the Latin participial stem of the verb and the suffix.[5] deduct is from Latin dēductus, the past participle of dēdūcō (“to lead down, bring away, withdraw”),[5][6] formed from dē- and dūcō (“to lead”), from Proto-Indo-European *deuk- (“to lead”).[5][6] The older adjective is deducible, from the 1610s.[6]

Earliest recorded meaning

That can be deducted, especially from one's tax or taxable income: first recorded in 1856, in Elizabeth Barrett Browning's Aurora Leigh.[5][4][6]

Semantic evolution

Merriam-Webster also records the adjective in the sense "deducible", the meaning that deduce and deduct once shared.[4][6] The noun, the part of a loss that the holder of an insurance policy has to bear, is recorded from 1927 and is chiefly North American;[5][6] Merriam-Webster dates it to 1929.[4] In Britain the same amount is usually called the excess.[7]

Timeline

  • 1856 – that can be deducted.[5][4][6]
  • 1927 – noun, the part of an insurance loss borne by the policyholder.[5][6] Merriam-Webster dates the noun to 1929.[4]

Meanings

Adjective

  1. That can be deducted, especially from taxable income: Charitable gifts are deductible.[7][4][5]
  2. (US and Canada) Short for tax-deductible.[7]
  3. Deducible.[4]

Noun

  1. (chiefly North America, insurance) The part of a claim that the policyholder must pay; in Britain, the excess: Their car insurance has a high deductible.[7][4][5]

Word family

  • deductibility
  • tax-deductible

References

  1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
  3. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
  4. ^ a b c d e f g h i Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
  5. ^ a b c d e f g h i Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
  6. ^ a b c d e f g h Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  7. ^ a b c d Collins English Dictionary (2023), Glasgow: HarperCollins

Related etymologies

Cite this entry

“Deductible.” Etymologically, 31 Oct. 2026, etymologically.com/en/deductible. Accessed 1 Nov. 2026.

Last edited on . ·