1. (n.) Anything that refracts

2. (n.) A refracting telescope, in which the image to be viewed is formed by the refraction of light in passing through a convex lens.

Cassegrainian telescope Newtonian telescope OAO OSO astronomical observatory astronomical telescope coelostat coronagraph coronograph heliostat observatory orrery planetarium radar telescope radio observatory radio telescope reflector spectrograph spectroheliograph spectrohelioscope spectroscope telescope