kinetics

Etymology

It is formed from English kinetic + -ics,^[2][3][4][5] in form a plural of the adjective.^[6] The adjective, recorded from 1841 in Etymonline and 1855 in the OED, is from Ancient Greek κινητικός (kīnētikós, “moving, putting in motion”),^[2][7][8] from κινητός (kīnētós, “moved”), the verbal adjective of κινέω (kinéō, “to move”),^[2][5] from Proto-Indo-European *keie- (“to set in motion”).^[2] Klein relates the Greek verb to Latin cieō (“to put in motion”) and citō (“to put into quick motion”), the source of cite, and compares cinema and kinematics.^[5]

Earliest recorded meaning

The branch of dynamics that studies how forces affect the motion of bodies: 1864, in Webster's American Dictionary of the English Language.^[6][2] Merriam-Webster Unabridged dates the word to about 1859.^[9] The OED notes that it was opposed to statics, the study of bodies at rest.^[6]

Semantic evolution

From the study of motion in mechanics, the word was taken into chemistry for the study of the rates and mechanisms of chemical reactions, from 1884, in M. M. P. Muir's Treatise on the Principles of Chemistry.^[6] From 1907 it was used for the rate and course of a particular process, the kinetics of a reaction, in which sense it is often construed as a plural.^[6][3] Collins records the sense of a branch of mechanics that includes both dynamics and kinematics, and gives the word as another name for dynamics.^[10]

Timeline

• 1864 – the branch of dynamics dealing with motion and the forces acting on bodies.^[6][2]
• 1884 – the study of the rates and mechanisms of chemical reactions.^[6]
• 1907 – the rate or mechanism of a particular process.^[6]

Meanings

Noun

1. The branch of mechanics or dynamics that studies the effect of forces on the motion of bodies.^[10][9][6]
2. The branch of physical science, especially chemistry, that studies the rates at which reactions and other changes take place: enzyme kinetics.^[10][9][6]
3. The rate and mechanism of a particular reaction or process: The kinetics of the process were studied at low temperature.^[9][6][3]

Word family

• biokinetics
• electrokinetics
• hydrokinetics
• pharmacokinetics

Related words

• kinetic
• kinematics
• cinema
• cite

Usage notes

The word is usually construed as singular, except in the sense of the rate or mechanism of a particular process, where it is often plural.^[3][6][10]

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
3. ^ a b c d Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
4. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
5. ^ a b c 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 i j k l Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
7. ^ Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
8. ^ Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
9. ^ a b c d Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
10. ^ a b c d Collins English Dictionary (2023), Glasgow: HarperCollins