photosynthesis

Etymology

It is formed from English photo- + synthesis.^[2][3][4] Barnhart and Etymonline call it a loan translation of German Photosynthese,^[5][6] but the revised OED shows that the English word came first: it was suggested in 1893 as an alternative to C. R. Barnes's term photosyntax, and its adoption was then helped by the German word in W. Pfeffer's “Pflanzenphysiologie” (1897).^[2] Merriam-Webster calls it New Latin.^[7] The first element is from Ancient Greek φῶς (phôs, “light”),^[6][2] and the second comes through Latin synthesis from Ancient Greek σύνθεσις (súnthesis, “a putting together”).^[6][2]

Earliest recorded meaning

The process by which plants use the energy of light absorbed by chlorophyll to build organic compounds: 1893, in C. R. Barnes's paper in the Botanical Gazette.^[2][8][7] Etymonline has it by 1895,^[6] and Barnhart from 1898.^[5]

Semantic evolution

Barnes proposed photosyntax at the Madison meeting of the American Association for the Advancement of Science in August 1893, to replace the vaguer assimilation; in the discussion Conway MacMillan suggested photosynthesis as etymologically more appropriate.^[2][6] Photosyntax won some acceptance at first,^[6][2] but photosynthesis found favour with American botanists and soon prevailed.^[2] From 1913 chemists also used the word for any synthesis brought about by light, a sense now rare.^[2] Barnhart dates photosynthetic to 1900 and the verb photosynthesize to 1921.^[5]

Timeline

• 1893 – the making of organic compounds by plants with the energy of light.^[2][7][8]
• 1913 – in chemistry, synthesis brought about by light.^[2]

Meanings

Noun

1. The process by which green plants use the energy of light, absorbed by chlorophyll, to make carbohydrates from carbon dioxide and water, usually releasing oxygen.^{[9][10][7][2]}
2. The similar process in certain bacteria.^[9][7]
3. (chemistry) The synthesis of a compound with the aid of light; now rare.^[2][7]

Word family

• photosynthetic
• photosynthetically
• photosynthate

Related words

• photosynthesize
• synthesis
• photon

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 Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ 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 Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
6. ^ a b c d e f Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
7. ^ a b c d e f Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
8. ^ a b Kay, Christian; Roberts, Jane; Samuels, Michael; Wotherspoon, Irené, eds. (2009), Historical Thesaurus of the Oxford English Dictionary, Oxford: Oxford University Press; online edition (2024)
9. ^ a b Collins English Dictionary (2023), Glasgow: HarperCollins
10. ^ The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin