dipleidoscope
Noun. (astronomy) An instrument for determining the time of apparent noon. It consists of two mirrors and a plane glass in the form of a prism, so that, by the reflections of the sun's rays from their surfaces, two images are presented to the eye, moving in opposite directions, and coinciding at the instant the sun's centre is on the meridian.This is an unmodified, but possibly outdated, definition from Wiktionary and used here under the Creative Commons license. Wiktionary is a great resource. If you like it too, please donate to Wikimedia.
This entry was last updated on RefTopia from its source on 3/20/2012.