substance vs thickness

substance and thickness both are nouns.

Word	Noun	Adjective	Verb	Adverb
substance	Yes	No	No	No
thickness	Yes	No	No	No

As nouns, thickness is a hyponym of substance; that is, thickness is a word with a more specific, narrower meaning than substance:

substance (noun)	thickness (noun)
the real physical matter of which a person or thing consists	the dimension through an object as opposed to its length or width
a particular kind or species of matter with uniform properties	resistance to flow
the property of holding together and retaining its shape	used of a line or mark
the idea that is intended	indistinct articulation
the choicest or most essential or most vital part of some idea or experience
content communicating a message; what something is about
considerable capital (wealth or income)
material of a particular kind or constitution