ethyl

Etymology

It is partly borrowed from German Ethyl, a name given by the German chemist Liebig in 1834 in the “Annalen der Pharmacie”, and partly formed from English eth- + -yl.^[2][3][4] A French translation of Liebig's paper, with éthyle, appeared in 1833, before the German original.^[2] The German word is formed from Äther (“ether”) and -yl,^[5][6][7] and the English word was modelled on it.^[7][8] The first element is ether,^[2][9][10] from Ancient Greek αἰθήρ (aithḗr, “the upper air”);^[11][3] the suffix -yl is -yle, from ὕλη (húlē, “wood; stuff, material”), introduced into chemical names by Liebig and Wöhler in 1832.^[3][11] Klein instead credits the Swedish chemist Berzelius with the word, in 1840.^[11]

Earliest recorded meaning

A hydrocarbon radical, at first given the formula C4H5 and thought to be present in ether: 1834, in the fifth edition of E. Turner's Elements of Chemistry.^[2] Merriam-Webster Unabridged also dates the word to 1834,^[12] Etymonline to 1838,^[3] and Barnhart to 1850.^[7][8]

Semantic evolution

The radical that Liebig named was later redefined as the group C2H5, which occurs in ethanol and its derivatives; the older sense is now only historical.^[2] Ethyl alcohol itself was widely used in medicine, under other names, by the 13th century, long before the word existed.^[3] From 1850 the word also named compounds of a metal with ethyl groups,^[2] and in the United States from 1923 it became a name for petrol containing the anti-knock additive tetraethyl lead, and for the additive itself.^[2] In the 19th century the spelling ethule was also used, reflecting the transliteration of the Greek letter upsilon as u.^[2]

Timeline

• 1834 – a hydrocarbon radical thought to be present in ether; later the group C2H5.^[2][12]
• 1850 – a compound of a metal with ethyl groups.^[2]
• 1923 – (US) petrol with a tetraethyl lead additive, or the additive itself.^[2]

Meanings

Noun

1. The univalent radical C2H5, derived from ethane by removing one hydrogen atom, as in ethanol: an ethyl group.^[12][10][2]
2. A compound in which ethyl groups are bonded to a metal atom, usually named with the metal.^[2]
3. (US) Petrol containing tetraethyl lead as an antiknock agent; also the additive itself.^[2]

Word family

• ethylic
• ethylamine
• ethylate
• ethylbenzene
• ethylene

Related words

• ether
• -yl
• methyl
• ethane
• ethanol

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 Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
5. ^ Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
6. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
7. ^ a b c Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
8. ^ a b Barnhart, Robert K., ed. (1995), The Barnhart Concise Dictionary of Etymology, New York: HarperCollins
9. ^ The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
10. ^ a b Collins English Dictionary (2023), Glasgow: HarperCollins
11. ^ a b c Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
12. ^ a b c Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster