An Oligotrophic refers to any environment which offers little to sustain life. This term is usually used to describe bodies of water with very low nutrient levels.
Greek etymology: Oligo : small, little, few and trophe : nutrients, food.
Oligotrophic environments are of special interest for the alternative energy sources and survival strategies life could rely upon.
Examples of oligotrophic environments
An especially fascinating example of such a lake is Lake Vostok, a liquid freshwater lake which has been isolated from the world beneath 4 km of Antarctic ice for approximately 500,000 years.