
1) Engine trial-run support 2) Laboratory, of a sort 3) Proving ground
Found on
https://www.crosswordclues.com/clue/testbed

A testbed (also commonly spelled as test bed in research publications) is a platform for experimentation of large development projects. Testbeds allow for rigorous, transparent, and replicable testing of scientific theories, computational tools, and new technologies. The term is used across many disciplines to describe a development environment th...
Found on
http://en.wikipedia.org/wiki/Testbed
No exact match found.