Etymologically
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reciprocal

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Pronunciation

  • /ɹɪˈsɪpɹək(ə)l/[1]

Etymology

It is borrowed from Latin reciprocus (“returning the same way, alternating”) with the suffix -al.[2][3][4][5][6] The Latin adjective is explained as *recoprocos, from *recos (“turning backward”), formed on re- (“back”), and *procos (“turning forward”), formed on pro- (“forward”);[3][7][8][5] so it first meant "going backward and forward".[8] Klein relates the second element to procul (“far off”).[8][9] Barnhart adds that attempts to take it further back into Indo-European have produced no convincing explanation.[4] English had earlier reciproque, from Middle French reciproque (1532), and Barnhart suggests that reciprocal was a deliberate Latinate replacement for it;[4][2] the OED notes that the adverb reciprocally is recorded slightly earlier.[2]

Earliest recorded meaning

Given or done in return, answering: 1567, in G. Fenton's translation of Bandello.[2][5] Barnhart and Etymonline date the word to 1570, Barnhart for the sense "inversely related",[4][3] which the OED finds the same year in Billingsley's translation of Euclid.[2]

Semantic evolution

The sense "felt or shared by both sides, mutual" appears in 1578 in Lyly's Euphues,[2] or 1579 in Barnhart,[4] and that of something exchanged between two parties in 1608, in Shakespeare's King Lear.[2] From the 1590s the word also described movement backward and forward, later chiefly in mechanics;[2][3] for this, the forms reciprocating, reciprocative and reciprocatory were also tried.[3] The sense "interchangeable, equivalent in meaning" was used from 1616 to 1733,[2] and Johnson (1755) still gave "mutually interchangeable" among its senses, after "alternate" and "mutual".[10] In grammar it came to mean reflexive in the 17th century,[7] and today names pronouns such as each other.[11] The mathematical sense, of a quantity whose product with another is one, goes back to Billingsley's Euclid (1570).[2][4]

Timeline

  • 1567 – given or done in return.[2][5]
  • 1570 – mathematics, inversely related; also as a noun.[2][4]
  • 1578 – existing on both sides, mutual.[2]
  • 1594 – moving backward and forward alternately.[2][3]
  • 1608 – exchanged by two parties.[2]
  • 1616 – interchangeable, equivalent (obsolete by 1733).[2]
  • 1632 – opposite, inversely corresponding.[2]
  • 1902 – physics, of units that measure the reciprocals of standard quantities.[2]

Meanings

Adjective

  1. Given, felt or done by each of two parties to the other; mutual: a reciprocal trade agreement.[11][2]
  2. Given or done in return: She helped him, expecting a reciprocal favour.[11][2]
  3. (grammar) Of a pronoun or verb: expressing an action that each subject does to the other, as each other.[11]
  4. (mathematics) Of a quantity: related to another so that their product is one.[11][2]
  5. Inversely related; opposite.[5][2]
  6. (nautical) Of a course or bearing: differing by 180 degrees from another.[11]
  7. (obsolete, 1616–1733) Interchangeable; equivalent in meaning.[2][10]

Noun

  1. Something that is reciprocal to something else.[5][4]
  2. (mathematics) A number that gives one when multiplied by a given number: The reciprocal of 5 is 1/5.[5][4]

Word family

  • reciprocality
  • reciprocally
  • nonreciprocal
  • unreciprocal
  • reciprocal pronoun
  • reciprocity
  • reciprocate
  • reciproque

References

  1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d e f g h i j k l m n o p q r s t u v w Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
  3. ^ a b c d e f Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  4. ^ a b c d e f g h i Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
  5. ^ a b c d e f g Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
  6. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
  7. ^ a b Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
  8. ^ a b c Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
  9. ^ Skeat, Walter W. (1911), A Concise Etymological Dictionary of the English Language, new ed., Oxford: Clarendon Press
  10. ^ 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.
  11. ^ a b c d e f Collins English Dictionary (2023), Glasgow: HarperCollins