What do you call a four sided figure that has only two sides parallel?

A four-sided figure that has only two sides parallel is identified as a trapezoid. This geometric shape is characterized by the presence of one pair of parallel sides, referred to as the bases, and the other pair as the legs, which are not parallel. This definition distinguishes trapezoids from other quadrilaterals.

A square and a rhombus each have four equal sides and angles, with squares having all angles as right angles, while rhombuses can have angles that are not right angles. A rhomboid, on the other hand, is defined as a parallelogram with adjacent sides of unequal lengths and angles that are not right angles, hence fulfilling the requirement of having opposite sides parallel but not a sole pair. Thus, in the context of the question, a trapezoid is the correct term that meets the specific criteria of having exactly one pair of sides parallel.