refract

Etymology

It is borrowed from Latin refractus, the past participle of refringō (“to break, to deflect light rays, to break open, to repel”),^[2][3][4][5] formed from re- (“back”) and frangō (“to break”),^[2][6][7] from Proto-Indo-European *bhreg- (“to break”),^[8][9] the root of break.^[3] Barnhart and Etymonline see in it a back-formation from refraction as well, Barnhart with the Latin participle only as a possible source of some instances.^[6][8] According to the OED, senses such as the figurative one and the ophthalmological one follow the corresponding senses of refraction, all recorded earlier.^[2]

Earliest recorded meaning

To deflect the course of light rays: 1563, in W. Fulke's Goodly Gallerye on the causes of meteors, according to the OED's entry revised in 2009.^[2][3] Barnhart and the Merriam-Webster Collegiate date it to 1612,^[6][10] Etymonline to the 1610s^[8] and the Shorter Oxford to the early 17th century.^[11]

Semantic evolution

In the 17th century the verb also kept closer to its Latin senses: to reflect or return (from 1621, in Burton, and now rare) and to break up or impair (1646–76, first in Browne).^[2][11] Johnson (1755) defined it as breaking the natural course of rays.^[12] The modern figurative sense of altering or distorting, as if by passing through a medium, dates from 1700.^[2][9][3] Later uses came from optics and its neighbours: to produce by refraction (1728, in Thomson), to undergo refraction (1888), and to measure the refractive error of an eye (1897).^[2] A chemical sense, analysing nitre for impurities, is recorded only in 1845–49.^[2]

Timeline

• 1563 – to deflect light rays.^[2][3]
• 1621 – to reflect, to return.^[2]
• 1646 – to break up, to impair (obsolete by 1676).^[2]
• 1700 – figuratively, to mediate or distort.^[2]
• 1728 – to produce by refraction.^[2]
• 1845 – to analyse nitre for impurities (obsolete by 1849).^[2]
• 1888 – intransitive, to undergo refraction.^[2]
• 1897 – to measure the refractive error of an eye.^[2]

Meanings

Verb

1. To bend the path of light, sound or other waves as they pass from one medium into another: A glass of water refracts the sunbeam.^{[9][13][3][2]}
2. To alter or distort, as if by passing through a medium: The novel refracts the war through a child's eyes.^[9][3][2]
3. In ophthalmology, to measure the refractive error of an eye or lens, often correcting it.^{[9][13][3][2]}
4. To undergo refraction.^[2][11]
5. (rare) To produce by refraction.^[2][11]
6. (obsolete or rare) To reflect or return.^[2][3][11]
7. (obsolete, 1646–1676) To break up; to impair.^[2][3][11]

Word family

• refractable
• refractedly
• refractedness
• refractometer
• refractor
• nonrefracting
• unrefracting
• refracting telescope

Related words

• refractive
• refraction
• refractory
• refrangible
• refringent
• fraction
• fracture
• fragile
• fragment
• break

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 g h i j Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
4. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
5. ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
6. ^ a b c Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
7. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
8. ^ a b c Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
9. ^ a b c d e The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
10. ^ Merriam-Webster's Collegiate Dictionary (2003), 11th ed., Springfield, Mass.: Merriam-Webster
11. ^ a b c d e f Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
12. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
13. ^ a b Collins English Dictionary (2023), Glasgow: HarperCollins