What is the definition of an acute triangle?

An acute triangle is defined as a triangle in which all three of its interior angles are less than 90 degrees. In such triangles, each angle is acute, contributing to the overall classification of the triangle. This property ensures that the triangle has a certain shape that is distinctly different from right triangles, which contain one angle that is exactly 90 degrees, and obtuse triangles, which have one angle greater than 90 degrees. The fact that all angles are less than 90 degrees is what distinctly characterizes an acute triangle. Understanding this definition is crucial in recognizing various types of triangles and their properties in geometry.