noun
A historical astronomical and navigational instrument for measuring angles up to 90 degrees. Also called 象限儀.
See also: 象限儀
四分儀は、天体の高度を測るのに使われた。
The quadrant was used to measure the altitude of celestial bodies.
A sextant, a similar instrument measuring up to 60 degrees, later replacing the quadrant.
From 四分 (quarter, four parts) + 儀 (instrument). The term refers to the instrument's 90-degree arc, which is a quarter of a circle.