Concrete
In his response at the end of Jesus and the Restoration of Israel, N. T. Wright draws some helpful distinctions:
Strictly speaking, the opposite of metaphorical is literal. These two words refer to the way words refer to things, not to the things themselves. Confusion arises, not least in present discussions, because this pair is regularly muddled up with the words abstract and concrete, which indicate not the way words refer to things but rather the sort of things words refer to. Thus “Plato’s theory of forms” refers, literally, to a doubly abstract entity (the forms themselves, by definition, are abstract, and the theory is an abstract idea about those abstractions). If I say “Plato’s whole box of tricks,” intending to refer to that same theory, I am referring metaphorically to the same abstract entity (or entities). Alternatively, if I talk about “my car,” I am referring literally to something concrete; and if I say “my old tin can,” I am referring metaphorically to that same concrete entity. Matters are made much worse because, in popular usage, literally is regularly used to add emphasis to a sentence without any serious intent to mean what it says (“we were literally driving at the speed of light”; “my grandfather is literally as old as the hills”). We are thus bereft of the literal meaning of literal, and we find ourselves wallowing in all too many metaphorical meanings of metaphorical (pp. 261-262).
In a footnote, Wright then adds this, which should be of interest to all the many concrete workers in my congregation:
The word concrete is interesting in itself. We today may think of it as referring literally to the compound regularly used in building and so on; hence, we may think of it as referring metaphorically, as in the last sentence, to solid physical entities as opposed to abstract ones. But its original meaning, from the Latin concrescere, had to do with the putting together of solids, so that the meaning “physical, nonabstract” is the more literal meaning and the meaning “the substance used in building” the more metaphorical (p. 318n23).
Confused yet?