Relating to the capability of synthesizing complex organic substances from simple inorganic substrates; including both the chemoautotrophic and the photoautotrophic organisms: An autotrophic form of life is one for which environmental carbon dioxide is the only or main source of carbon in the synthesis of organic compounds by photosynthesis.

A body of water surrounded by land in which all or most of the organic matter present is derived from within the lake and not from drainage off the surrounding land: Autotrophic lakes are an aquatic ecosystems that are especially productive nutrient rich environments.