trapezoid vs quadrilateral

trapezoid and quadrilateral both are nouns.

Word	Noun	Adjective	Verb	Adverb
trapezoid	Yes	No	No	No
quadrilateral	Yes	Yes	No	No

As nouns, quadrilateral is a hypernym of trapezoid; that is, quadrilateral is a word with a broader meaning than trapezoid:

Other hypernyms of trapezoid include quadrangle, tetragon.

trapezoid (noun)	quadrilateral (noun)
the wrist bone between the trapezium and the capitate bones	a four-sided polygon
a quadrilateral with two parallel sides

trapezoid (adjective)	quadrilateral (adjective)
	having four sides