deflection

Etymology

It is borrowed from Latin dēflexiō (“a bending aside or downward”),^[2][3][4] a noun of action from dēflectō (“to bend aside or downward”), whose past participle is dēflexus.^[2][3][5] The Latin verb is formed from dē- (“away”) and flectō (“to bend”), which is of uncertain origin.^[3] Klein and the Shorter Oxford call the noun Late Latin.^[4][6] The variant deflexion is the etymological spelling.^[2][3] The now usual spelling is taken from the present stem of the verb, after nouns such as collection and dissection.^[2] French has déflexion, with a 16th-century variant déflection.^[2][6] It is related to deflect.^[3][4]

Earliest recorded meaning

A turning of a word or phrase away from its proper form or use: 1603, in Philemon Holland's translation of Plutarch's Moralia, a sense now archaic.^[2] Etymonline dates the noun to about 1600,^[3] and Merriam-Webster dates its sense of turning aside to 1605.^[5]

Semantic evolution

From 1605, in Bacon, the word was used of abstract things turned from their course.^[2] From 1646, in Sir Thomas Browne, it was used of a magnetic needle turning away from its zero.^[2] Johnson (1755) quoted Browne for "deviation; the act of turning aside".^[2][7] In 1665 it appears for physical bending and for turning away from a straight path, the main modern sense.^[2] Later technical uses include the bending of light rays in optics (before 1703, in Hooke) and a ship's departure from its course (1706).^[2] Both spellings were current in the 17th century, but the one with c has since prevailed.^[3] Collins records the one with x as a British variant.^[8][9]

Timeline

• 1603 – the turning of a word from its form or use (now archaic).^[2]
• 1605 – a turning aside of something abstract, in Bacon.^[2][5]
• 1646 – the turning of a magnetic needle from zero.^[2]
• 1665 – a bending or curving; a turning from a straight line.^[2]
• before 1703 – in optics, the bending of light rays.^[2]
• 1706 – a ship's deviation from its course.^[2]

Meanings

Noun

1. The act of turning aside, or the state of being turned aside, from a straight course: the deflection of the ball off a defender.^[8][5][2]
2. The amount of such a turning aside.^[8][2]
3. The movement of the needle or pointer of a measuring instrument away from its zero.^[8][2]
4. The bending of a structural part under a load, or the amount of it.^[5][2]
5. The change of direction of a beam of light, as when it passes from one medium into another.^[8][2]

Related words

• deflect
• flexible
• reflection

References

1. ^ a b 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 Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e f g Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b c Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
5. ^ a b c d e Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
6. ^ a b Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
7. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
8. ^ a b c d e Collins English Dictionary (2023), Glasgow: HarperCollins
9. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House