In the shape of a trapezoid, or having some faces which have one pair of parallel sides.(adjective)
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Use "trapezoidal" in a sentence
"Its messenger was not a religious work of art, but a pagan one: the ancient bronze statue of the Emperor Marcus Aurelius 121–180 riding his horse, in the most noble silence and stillness, on a pedestal that rose from the center of a 12-pointed star, in the trapezoidal piazza Michelangelo designed for the Campidoglio."
"The five-story trapezoidal house was the home of Patricia and Francis Mason ."
"From the kitchen window, I could see a trapezoidal sliver of Mediterranean water, which was a different color every day, a giant mood ring for the city."