Is a word derived from the words 'permanent' and 'agriculture' to describe a system of design applied to agricultural and human systems to mimic natural ecosystems where everything in the system is an input or output for other parts and nothing is lost outside the system. In other words, permanent, self-sustaining systems - like our old-growth rainforests were before being devastated by logging, clearing for agriculture or mining.
Permaculture focuses not only on organic growing of our food but also on how we live in our environment. It could be described as the only all-embracing design system for sustainable living. It might just be the thing that helps us break the cycle of unsustainable living that has deforested much of our planet, degraded soils, polluted the rivers and air, led to the extinction of many species of fauna and flora important to their ecosystems and visited large scale health problems on the human population.