Which of the following is INCORRECTLY spelled.

The word Trapezum is incorrectly spelled. The correct spelling is Trapezium.

Here are the words and their correct spellings:

• Trapezium means a four-sided shape with one set of parallel sides.
• Parallelogram means a four-sided shape with two sets of parallel sides.
• Quadrangular means having four angles.
• Pentagonal means having five angles.