■ noun an early reflecting telescope in which light reflected from a concave elliptical secondary mirror passes through a hole in the primary mirror.
Origin
C18: named after the 17th-cent. Scottish mathematician James Gregory .
■ noun an early reflecting telescope in which light reflected from a concave elliptical secondary mirror passes through a hole in the primary mirror.
Origin
C18: named after the 17th-cent. Scottish mathematician James Gregory .
Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004