cam·er·a ob·scu·ra
/ˌkam(ə)rə əbˈskyo͝orə/
noun
a darkened box with a convex lens or aperture for projecting the image of an external object onto a screen inside. It is important historically in the development of photography.
a small round building with a rotating angled mirror at the apex of the roof, projecting an image of the landscape on to a horizontal surface inside.
