Which type of angle measures greater than 180 degrees but less than 360 degrees?

A reflex angle is defined as an angle that measures greater than 180 degrees but less than 360 degrees. This type of angle essentially represents the larger arc created when two rays originate from a common vertex and form an angle that opens outward beyond the straight line (180 degrees) but does not complete a full circle (360 degrees).

In contrast, acute angles measure less than 90 degrees, obtuse angles measure more than 90 degrees but less than 180 degrees, and straight angles are exactly 180 degrees. Therefore, the unique measure of a reflex angle falling within the range of 180 to 360 degrees makes it the correct response to the question.