reflex

Etymology

It is borrowed from Latin reflexus (“a bending back, turning point”),^[2][3][4][5] a verbal noun formed from reflex-, the past participial stem of reflectō (“to bend back”),^[2][3] itself formed from re- (“back”) and flectō (“to bend”).^[3] The OED thinks the early sense "reflected light" was perhaps modelled on Italian riflesso, and compares Middle French reflexe (1432) and Spanish reflejo;^[2] Barnhart takes the noun from the English verb, and partly from the Middle French word.^[6] The adjective is the Latin past participle, meaning "bent back", used as an adjective, and in later use partly the noun.^[2][6][5] The verb is first found as inherited from Middle English reflexen (“to refract, deflect”), from the same participle;^[7][3][6] reflect comes from the same Latin verb.^[3][4]

Earliest recorded meaning

The verb, to refract or deflect light: before 1425, in a Wycliffite sermon.^[7][6] The noun first meant reflected light or the reflection of light, in 1508 in Dunbar's Goldyn Targe.^[2][6][8]

Semantic evolution

In the 16th and 17th centuries the word kept close to reflect: the noun was used for a mirror image (1596–1850), for turning the mind back upon a subject, that is, meditation (1593–1657), and for a sidelong glance or allusion (1630–50),^[2][8] and the adjective, from 1607, for thought that turns back upon itself.^[2][8] Barnhart and Etymonline date the adjective to the 1640s.^[6][3] Johnson (1755) knew only this adjective, "directed backward", as in "the reflex act of the soul".^[9] The physiological sense, an action done without conscious thought in response to a stimulus, comes from M. Hall's paper of 1833 in the Philosophical Transactions, where reflex is used both as a noun and as an adjective;^[2][3] Barnhart and Etymonline find the noun in this sense only in 1877, short for reflex action.^[6][3] Other languages took this use from English.^[2] Later senses include a form developed from an earlier one in linguistics (1880), a reflex camera (1922) and, in reflexology, a point on the foot linked to another part of the body (1948).^[2]

Timeline

• before 1425 – verb, to refract or deflect light.^[7]
• 1508 – noun, reflected light, in Dunbar.^[2][6][8]
• c. 1536 – verb, to reflect light (obsolete by 1658).^[2]
• c. 1570 – verb, to bend or turn back.^[2]
• 1593 – meditation, reflection (obsolete by 1657).^[2]
• 1607 – adjective, of thought that turns back upon itself.^[2][8]
• 1633 – adjective, bent or turned back, in botany.^[2]
• 1833 – an involuntary action in response to a stimulus.^[2][3]
• 1880 – in linguistics, a form developed from an earlier one.^[2]
• 1922 – a reflex camera.^[2]

Meanings

Noun

1. An automatic, involuntary response to a stimulus, such as coughing or pulling the hand away from a hot surface.^[10][8][2]
2. An action done mechanically, without conscious decision: He reached for the phone out of reflex.^[10][2]
3. A reflection, or an image or copy that reproduces the features of an original.^[10][8][2]
4. (linguistics) A word or sound that has developed from a corresponding form in an earlier stage of the language.^[10][2]
5. A reflex camera.^[2]
6. Reflected light or colour, especially in painting.^[8][2]
7. (obsolete, 1593–1657) Meditation; a considered thought or statement.^[2][8]
8. (obsolete, 1630–50) A glance, or an indirect reference.^[2][8]

Adjective

1. Done automatically, without the will, in response to a stimulus: a reflex reaction.^[10][8][2]
2. Bent, turned or directed back.^[8][2]
3. Directed back upon the mind; introspective.^[8][2][9]
4. Produced in reaction or in return.^[8]
5. Of an angle, between 180° and 360°.^[8]

Verb

1. To bend or turn back.^[2][11]
2. (obsolete, c. 1536–1658) To reflect light.^[2][11]

Word family

• reflexly
• reflexness
• chemoreflex
• multireflex
• reflexology
• semireflex

Related words

• reflect
• reflection
• reflexive
• flex
• flexible
• retroflex

Usage notes

The OED notes that the noun was commonly stressed on the second syllable until the 19th century, as the metre of older poetry shows; the first edition of the OED (1905) gave only that stress for the verb.^[2]

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 x y z 27 28 29 30 31 32 33 Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e f g h i Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
5. ^ a b Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
6. ^ a b c d e f g h Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
7. ^ 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)
8. ^ a b c d e f g h i j k l m n o Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
9. ^ 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.
10. ^ a b c d e Collins English Dictionary (2023), Glasgow: HarperCollins
11. ^ a b Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press