Hi Don. I note you are writing to us from Canada, therefore the North American definition of trapezoid applies.

No. In order for a quadrilateral to be a trapezoid, it must have exactly one pair of parallel sides. A right trapezoid, therefore, has exactly one pair of right angles. However a square would be a right parallelogram (which is the current definition of a rectangle).

In the UK, the word trapezoid refers to a quadrilateral with no sides parallel. They use the word trapezium to refer to what Canadians call a trapezoid. To make matters worse, North Americans call a quadrilateral with no parallel sides a trapezium. Here's a summary.

Stephen La Rocque.

PS: We have a mathematical glossary that you may find useful.