Vertically opposite
Right angle
Acute angle
Revolution 
180
90
360
Obtuse

Acute Angle – An Acute angle is any angle less than 90°.

Obtuse – An Obtuse angle is an angle greater than 90° but less than 180°.

Reflex – A Reflex angle greater than 180° but less than 360°.

Right Angle – A Right Angle, as we saw above, is an angle of exactly 90°.

adjacent angles nountwo angles that are formed when one angle is divided into two parts by a straight line

angle nounmaths the shape that is made where two straight lines join or cross each other. Angles are measured in degrees. An angle that measures 90 degrees is a right angle; if it is less than 90 degrees, it is an acute angle, and if it is more than 90 degrees, it is an obtuse angle.

angle nounthe shape that is made where two surfaces or objects meet

azimuth nounthe angle of the imaginary line between the position of a plane, ship etc and the position of another object

cant nounthe difference in height between one side of a road or railway and the other

complement nounmaths an angle that is added to another angle to form an angle of 90 degrees

complementary angles nountwo angles that together form a right angle

corresponding angles nounthe two inside corner angles formed where a straight line crosses two parallel lines

crook nounthe place where something bends inwards

inclination nouna slope, or the angle of a slope

lean nouna slope, or an angle

obtuse angle nounany angle that is between 90° and 180°

opposite angles nounthe angles opposite each other that are formed when two lines intersect (=cross each other)

reflex angle nounan angle that is between 180° and 360°

right angle nounan angle of 90°

round angle nounan angle of 360°

straight angle nounan angle of 180°

supplementary angles nountwo angles that make 180° when they are added together

vertex nounmaths the point that is opposite the base of a triangle