diagonal vs square matrix

diagonal and square matrix both are nouns.

Word	Noun	Adjective	Verb	Adverb
diagonal	Yes	Yes	No	No
square matrix	Yes	No	No	No

diagonal (noun)	square matrix (noun)
a punctuation mark (/) used to separate related items of information	a matrix with the same number of rows and columns
an oblique line of squares of the same color on a checkerboard
(mathematics) a set of entries in a square matrix running diagonally either from the upper left to lower right entry or running from the upper right to lower left entry
a line or cut across a fabric that is not at right angles to a side of the fabric
(geometry) a straight line connecting any two vertices of a polygon that are not adjacent

diagonal (adjective)	square matrix (adjective)
having an oblique or slanted direction
connecting two nonadjacent corners of a plane figure or any two corners of a solid that are not in the same face