Any angle that is more than 180° but less than 360 is called a reflex angle. See the below images:
Facts about Reflex angle:
A reflex angle is always equal to the sum of 180 degrees and any one of the primary angles such as acute angle, right angle, and obtuse angles).
Examples:
Reflex angle = 180° + Acute angle
Reflex angle = 180° + Right angle
Reflex angle = 180° + Obtuse angle