If something is renewable, it is capable of being replaced through sound management practices or by natural ecological cycles. It is not used up like a finite resource.
The word "renewable" dates back to 1727 from the stem "renew" and the suffix "able." Using the word in reference to energy sources started in 1971. A renewable resource is one that can be replenished over the passage of time through biological reproduction and other natural processes. These include wind, sunlight and water resources. A renewable contract is one that can be continued for a longer period of time than the original.