the inverse function of the tangent; the angle that has a tangent equal to a given number

a buttress that stands apart from the main structure and connected to it by an arch

the inverse function of the tangent; the angle that has a tangent equal to a given number

a straight line or plane that touches a curve or curved surface at a point but does not intersect it at that point

ratio of the opposite to the adjacent side of a right-angled triangle

electrical conduction through a gas in an applied electric field

a continuous portion of a circle

something curved in shape