the GNU version of the Collaborative International Dictionary of English
adj. Having the form of a trapezium; trapezoid.
The Century Dictionary and Cyclopedia
Having the shape of a trapezium.
In zoology, trapezoidal.
Word Usage
"The famous Kaaba, which is in the middle of the great court-yard, looked at a distance like an enormous cube, covered with a black curtain, but its plan is really trapeziform."