physical substance in general, as distinct from mind and spirit; (in physics) that which occupies space and possesses rest mass, especially as distinct from energy.
the structure and properties of matter
an affair or situation under consideration; a topic.
a great deal of work was done on this matter
the reason for distress or a problem.
what's the matter?
the substance or content of a text as distinct from its manner or form.
It's also not a show that's performed very often - and having seen the content matter , I can see why.