Gregorian telescope

noun

: a reflecting telescope that has a paraboloidal primary mirror with a perforation through which light is reflected to the eyepiece and an ellipsoidal secondary mirror set beyond the focus and that produces an erect image but a small field of view

Word History

Etymology

James Gregory †1675 Scottish mathematician and inventor + English -an

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Cite this Entry

“Gregorian telescope.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Gregorian%20telescope. Accessed 7 Feb. 2023.

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