Sustainability could be defined as an ability or capacity of something to be maintained or to sustain itself. It’s about taking what we need to live now, without jeopardising the potential for people in the future to meet their needs.
Source: http://www.landlearnnsw.org.au/sustainability/what-is-sustainability
Oxford Dictionary: able to be maintained at a certain rate or level
Merriam Dictionary: able to be used without completely use up or destroy natural resources.
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