Definition from Wiktionary, the free dictionary
trapezoid (plural trapezoids)
- (geometry) A (convex) quadrilateral with two (non-adjacent) parallel sides.
- (anatomy) The trapezoid bone of the wrist.
- (geometry, UK, obsolete) A convex quadrilateral with no sides parallel and no equal sides.
- (geometry, convex quadrilateral with two non-adjacent parallel sides): (British) trapezium
- (geometry, (obsolete) convex quadrilateral with no parallel sides): irregular quadrilateral, (US) trapezium
Derived terms 
quadrilateral with two sides parallel
quadrilateral with no sides parallel