adjective /trænsˈpærənt,trænzˈpærənt/
a) See-through, clear; having the property that light passes through it almost undisturbed, such that one can see through it clearly.
The waters of the lake were transparent until the factory dumped wastes there.
b) Open, public; having the property that theories and practices are publicly visible, thereby reducing the chance of corruption.
"You make the glass invisible by putting it into a liquid of nearly the same refractive index; a transparent thing becomes invisible if it is put in any medium of almost the same refractive index."
Wikipedia foundation.