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
photosynthesizeplay \ˌfō-tō-ˈsin(t)-thə-ˌsīz\ intransitive verb
photosyntheticplay \ˌfō-tō-sin-ˈthe-tik\ adjective
photosyntheticallyplay \ˌfō-tō-sin-ˈthe-ti-k(ə-)lē\ adverb
Recent Examples of photosynthesis from the Web
The new paper looks at two methods of photosynthesis in particular: C3 and C4, named after the structure of the molecules the methods produce.
Plants make their own food through photosynthesis, a process that utilizes the energy of the sun to create sugar from carbon dioxide and water.
Cheaper than trees or high-tech scrubber systems, oceanic plankton uses carbon dioxide during photosynthesis and plays a vital role in the global carbon cycle.
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.
Did You Know?
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.
Origin and Etymology of photosynthesis
First Known Use: 1898See Words from the same year
PHOTOSYNTHESIS Defined for English Language Learners
Definition of photosynthesis for English Language Learners
biology : the process by which a green plant turns water and carbon dioxide into food when the plant is exposed to light
PHOTOSYNTHESIS Defined for Kids
Definition of photosynthesis for Students
: 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
photosynthetic\-sin-ˈthe-tik\ adjective photosynthetic activity
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
photosynthesize\-ˌsīz\play also British
Learn More about photosynthesis
Spanish Central: Translation of photosynthesis Nglish: Translation of photosynthesis for Spanish speakers Britannica.com: Encyclopedia article about photosynthesis
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