A monoquadrilateral is a geometric figure defined as a quadrilateral that has only one type of angle, meaning all its angles are either acute, right, or obtuse. This characteristic leads to specific classifications within quadrilaterals, such as rectangles or rhombuses, depending on the angle type. Monoquadrilaterals can help in understanding certain properties and relationships in geometry. However, the term is not commonly used in standard geometry discussions and may appear in more specialized contexts.