PHOTOSYNTHESIS

n. (Biology) process of using sunlight to produce carbohydrates (esp. in plants)

Photosynthesis is the conversion of light energy into chemical energy by living organisms. The raw materials are carbon dioxide and water, the energy source is sunlight, and the end-products include glucose and oxygen. It is arguably the most important biochemical pathway, since nearly all life depends on it. It is a complex process occurring in higher plants, phytoplankton, algae, as well as bacteria such as cyanobacteria. Photosynthetic organisms are also referred to as photoautotrophs.
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Photosynthesis /pho·to·syn·the·sis/ a chemical combination caused by the action of light; specifically, the formation of carbohydrates from carbon [more]Photosynthesis - Community and Resources

Noun
1. synthesis of compounds with the aid of radiant energy (especially in plants)
(hypernym) chemical process, chemical change, chemical action
(part-meronym) light reaction
(classification) plant, flora, plant life

The manufacture by plants of carbohydrates and oxygen from carbon dioxide mediated by chlorophyll in the presence of sunlight.