photosynthesis

noun
pho·​to·​syn·​the·​sis | \ ˌfō-tō-ˈsin(t)-thə-səs How to pronounce photosynthesis (audio) \

Definition of photosynthesis

: synthesis of chemical compounds with the aid of radiant energy and especially light especially : formation of carbohydrates from carbon dioxide and a source of hydrogen (such as water) in the chlorophyll-containing cells (as of green plants) exposed to light

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Other Words from photosynthesis

photosynthesize \ ˌfō-​tō-​ˈsin(t)-​thə-​ˌsīz How to pronounce photosynthesize (audio) \ intransitive verb
photosynthetic \ ˌfō-​tō-​sin-​ˈthe-​tik How to pronounce photosynthetic (audio) \ adjective
photosynthetically \ ˌfō-​tō-​sin-​ˈthe-​ti-​k(ə-​)lē How to pronounce photosynthetically (audio) \ adverb

Photosynthesis Has Greek Roots

The Greek roots of photosynthesis combine to produce the basic meaning "to put together with the help of light". Photosynthesis is what first produced oxygen in the atmosphere billions of years ago, and it's still what keeps it there. Sunlight splits the water molecules (made of hydrogen and oxygen) held in a plant's leaves and releases the oxygen in them into the air. The leftover hydrogen combines with carbon dioxide to produce carbohydrates, which the plant uses as food—as do any animals or humans who might eat the plant.

Examples of photosynthesis in a Sentence

Recent Examples on the Web The plants also absorb carbon through photosynthesis, which Exxon scientists are trying to speed up while producing more oil. Clifford Krauss, New York Times, "U.S. and European Oil Giants Go Different Ways on Climate Change," 21 Sep. 2020 The process is called photosynthesis (fo-toe-SYN-thuh-sis). Paul Douglas, Star Tribune, "More Late August Than Late September, But Big Changes Next Week," 21 Sep. 2020 The process is called photosynthesis (fo-toe-SYN-thuh-sis). Washington Post, "Ever wondered why trees ditch their leaves each fall?," 20 Sep. 2020 Deciduous trees shed their leaves prior to the dark days of winter, when photosynthesis becomes impractical, though not before a lack of chlorophyll allows the leaves' true colors to briefly appear. Chris M. Worrell, cleveland, "Greater Cleveland overlooks provide miles of colorful fall foliage," 17 Sep. 2020 Simply put, the device has a UV catalyst core that decomposes odor through natural photosynthesis to produce clean air as a result. Popular Science, "Check out the best deals on home gadgets this week," 3 Sep. 2020 Chemically, carbon 14 behaves exactly like its stable siblings (carbon 12 and carbon 13), allowing plants to absorb it during photosynthesis and then pass it up the food chain. Scott Hershberger, Scientific American, "How Do Scientists Determine the Ages of Human Ancestors, Fossilized Dinosaurs and Other Organisms?," 4 Aug. 2020 For example, apart from contributing to global warming, rising carbon dioxide levels increase the amount of pollen that plants produce as a consequence of higher rates of photosynthesis. Neelu Tummala, Scientific American, "What Climate Change Does to the Human Body," 29 Aug. 2020 On land, most of the photosynthesis which provides the biomass and energy needed for life takes place in plants. The Economist, "The viral universe Viruses have big impacts on ecology and evolution as well as human health," 20 Aug. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'photosynthesis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of photosynthesis

1898, in the meaning defined above

History and Etymology for photosynthesis

New Latin

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Time Traveler for photosynthesis

Time Traveler

The first known use of photosynthesis was in 1898

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Statistics for photosynthesis

Last Updated

16 Oct 2020

Cite this Entry

“Photosynthesis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/photosynthesis. Accessed 24 Oct. 2020.

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More Definitions for photosynthesis

photosynthesis

noun
How to pronounce photosynthesis (audio)

English Language Learners Definition of photosynthesis

biology : the process by which a green plant turns water and carbon dioxide into food when the plant is exposed to light

photosynthesis

noun
pho·​to·​syn·​the·​sis | \ ˌfō-tə-ˈsin-thə-səs How to pronounce photosynthesis (audio) \

Kids Definition of photosynthesis

: the process by which green plants and a few other organisms (as some protists) form carbohydrates from carbon dioxide and water in the presence of light

Other Words from photosynthesis

photosynthetic \ -​sin-​ˈthe-​tik \ adjective photosynthetic activity

photosynthesis

noun
pho·​to·​syn·​the·​sis | \ ˌfōt-ō-ˈsin(t)-thə-səs How to pronounce photosynthesis (audio) \
plural photosyntheses

Medical Definition of photosynthesis

: synthesis of chemical compounds with the aid of light sometimes including the near infrared or near ultraviolet especially : the formation of carbohydrates from carbon dioxide and a source of hydrogen (as water) in chlorophyll-containing cells (as of green plants) exposed to light involving a photochemical release of oxygen through the decomposition of water followed by various enzymatic synthetic reactions that usually do not require the presence of light

Other Words from photosynthesis

photosynthesize \ -​ˌsīz How to pronounce photosynthesize (audio) \ also British photosynthesise intransitive verb photosynthesized also British photosynthesised; photosynthesizing also British photosynthesising
photosynthetic \ -​sin-​ˈthet-​ik How to pronounce photosynthetic (audio) \ adjective
photosynthetically \ -​i-​k(ə-​)lē How to pronounce photosynthetically (audio) \ adverb

More from Merriam-Webster on photosynthesis

Nglish: Translation of photosynthesis for Spanish Speakers

Britannica.com: Encyclopedia article about photosynthesis

Comments on photosynthesis

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