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

Semi-artificial photosynthesis, a relatively new field of study, aims to address those concerns by combining manmade technologies with biological processes in order to mimic nature’s method of splitting water into oxygen and hydrogen. Fox News, "Scientists invent way to create 'unlimited renewable energy'," 7 Sep. 2018 Some new development like photosynthesis, some new surprise like an asteroid or a belch of volcanic carbon, throws a monkey wrench into the world order. Robert M. Thorson, WSJ, "‘Timefulness’ Review: Thinking in Eons," 30 Dec. 2018 Artificial photosynthesis has been around for decades, but scientists haven’t been able to develop it on a scale large enough to support an industrial level, or that could operate without the use of expensive or polluting devices. Fox News, "Scientists invent way to create 'unlimited renewable energy'," 7 Sep. 2018 Plants around the world absorbed those isotopes during photosynthesis, effectively turning them into a time stamp. Moises Velasquez-manoff, New York Times, "Can Dirt Save the Earth?," 18 Apr. 2018 Here on Earth, 21 percent of our atmosphere is made up of oxygen — thanks to the abundance of plants and other organisms that create oxygen as a byproduct of photosynthesis. Deborah Netburn, The Seattle Times, "Mars could have enough molecular oxygen to support life," 26 Oct. 2018 Properly managed woodlands help avoid emissions by not burning the trees and also draw carbon dioxide from the atmosphere through photosynthesis. Fred Krupp, WSJ, "Harness the Market to Manage the Climate," 15 Oct. 2018 When days begin to grow shorter, deciduous (green leafy) trees start signaling their leaves to stop producing chlorophyll, the green pigment responsible for the leaves’ color and photosynthesis. Brian Resnick, Vox, "When and where fall foliage colors will peak, in one map," 13 Oct. 2018 In high tide, when less light reaches the alga, the crystals may capture some of the sunlight and pass it on to the surrounding chloroplasts for photosynthesis. Kai Kupferschmidt, Science | AAAS, "Scientists uncover the secret behind shimmering seaweed," 13 Apr. 2018

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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Last Updated

17 Mar 2019

Look-up Popularity

Time Traveler for photosynthesis

The first known use of photosynthesis was in 1898

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More Definitions for photosynthesis

photosynthesis

noun

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

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More from Merriam-Webster on photosynthesis

Spanish Central: Translation of photosynthesis

Nglish: Translation of photosynthesis for Spanish Speakers

Britannica.com: Encyclopedia article about photosynthesis

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