quad·rant
noun/ˈkwɒdrənt/
/ˈkwɑːdrənt/
- (geometry) a quarter of a circle or of its circumference (= the distance around it)
enlarge image四分之一圆（或圆周）；象限 - an instrument for measuring angles, especially to check your position at sea or to look at stars
象限仪，四分仪（常用于测量海上方位或观看星辰）
Word Originlate Middle English (denoting the astronomical instrument): from Latin quadrans, quadrant- ‘quarter’, from quattuor ‘four’.