Acute Angle Definition

In geometry, an acute angle is defined as an angle smaller than a right angle or 90°. In contrast, an angle more significant than a straight and acute angle lies between 180 to 360° is known as a reflex angle. Moreover, an acute angle can be used to measure a right angle.

However, it doesn’t imply that how much an angle is smaller than 90 degrees.

For instance, all the angles are formed by a triangle where each side is less than 90 degrees is known as an acute angle triangle.

For a more precise understanding, let us have an example below:

acute angel


To know about acute triangle, you can use our Acute Triangle Definition.