A sandbox is a testing environment that isolates untested code changes and outright experimentation from the production environment or repository. Sandboxes replicate at least the minimal functionality needed to accurately test the programs or other code under development (Source: WikiPedia)
Merriam-Webster Online Dictionary
sandbox (noun) a box or receptacle containing loose sand as
a) a shaker for sprinkling sand on wet ink
b) a box that contains sand for children to play in
