What is the meaning of "Abstract", and just how abstract can "Abstract" be?

[xJeremyx]

[Guy13]

You can simply put my picture by word and everyone would have a good sense of it.

Abstract IS what Concrete IS NOT which incorporates theoretical, undefinable, and abstruse. For a relational understanding, holes or shadows, even if they do exist, are abstract in its conception and its being or non-being.

There is both a lingual and metaphysical distinction that can be expressed from a concrete noun such as Blue but its Blueness, or degree of Blue, is metaphysical and undeniably abstract.

In essence Blue can be teal, navy, cobalt, powder, indigo, royal etc, as well as, all and none of these at once,

therefore,

Blue as Primary Color IS Concrete but Blueness, in all its blending (s), components, and forms are abstract metaphysical conceptions that at best are theoretically Blue and at worse wholly undefinable Abstraction in it multiplicity...

Hope this is helpful.