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 (as water) in the chlorophyll-containing cells (as of green plants) exposed to light
photosynthesizeplay \-ˌsīz\ intransitive verb
photosyntheticplay \-sin-ˈthe-tik\ adjective
photosyntheticallyplay \-ti-k(ə-)lē\ adverb
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: 1898
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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