secant
noun [ C ] mathematics specialized uk/ˈsiː.kənt/ us/ˈsiː.kənt/
正割
in a triangle that has one angle of 90°, the ratio of the hypotenuse (= the length of the side opposite the 90° angle) to the length of the side next to an angle less than 90°
割线
a line that crosses a circle at two places