obtuse angle – an angle that measures more than 90° but less than 180°

(pronounced ob-tyoos)

To remember the meaning of obtuse angle, use the following mnemonic:

The obstacle I'd choose (obtuse) to climb is the one with the angle greater than 90°. I couldn't do the other one.

An obtuse angle is greater than the right angle (90°), but smaller than a straight angle (180°).

Think of an obtuse angle as one that looks "wide" or "opened up" compared to a right angle.

For example:

Example 1

The lounger is reclined at an obtuse angle.

Example 2

The book is open at an obtuse angle.

The word "obtuse" itself comes from Latin meaning "blunt" or "dull", which describes the appearance of these wide angles.