an instrument used in astronomy for determining the declination and right ascension of stars. It consists of a telescope attached to a graduated circle
meridian circle in American English
noun
Astronomy
a transit instrument provided with a graduated vertical scale, used to measure the declinations of heavenly bodies and to determine the time of meridian transits
Also called: circle, transit circle, transit instrument
Word origin
[1540–50]This word is first recorded in the period 1540–50. Other words that entered Englishat around the same time include: flare, gondola, machine, platform, vacuum