An optical projector instrument that can project both transparent slides and opaque objects onto a screen.
From Greek 'epi' (upon) + 'dia' (through) + 'scope' (to view). Developed in early 20th-century optical technology, it combined the functions of a diascope and episcope.
Before PowerPoint, teachers used epidiascopes in classrooms—and this one device could project both slides AND actual 3D objects on a screen, making it the multi-tool of old-school presentations!
Complete word intelligence in one call. Free tier — 50 lookups/day.