serious vs solid

serious is not a noun while solid is a noun.

Word	Noun	Adjective	Verb	Adverb
serious	No	Yes	No	No
solid	Yes	Yes	No	No

serious (noun)	solid (noun)
	a three-dimensional object, structurally rigid, usually resistant to changes of shape or volume
	the state in which a substance has no tendency to flow under moderate stress; resists forces (such as compression) that tend to deform it; and retains a definite size and shape
	matter that is solid at room temperature and pressure

serious (adjective)	solid (adjective)
concerned with work or important matters rather than play or trivialities	of definite shape and volume; firm; neither liquid nor gaseous
completely lacking in playfulness	entirely of one substance with no holes inside
causing fear or anxiety by threatening great harm	having length, breadth and thickness
requiring effort or concentration; complex and not easy to answer or solve	characterized by good substantial quality
of great consequence	not soft or yielding to pressure
appealing to the mind	of one substance or character throughout
	impenetrable for the eye
	meriting respect or esteem
	of a substantial character and not frivolous or superficial
	financially dependable
	of good quality and condition; solidly built
	uninterrupted in space; having no gaps or breaks
	acting together as a single undiversified whole
	providing abundant nourishment
	of the same color throughout