The best use of "magic" I've seen came from a kids TV show where the protagonist would simply refer to new or mysterious things as "magic" even if the other characters offered him an explanation of how the thing worked. To me it was a perfect example of black-box abstraction.
Its magic because we know what it is doing, but the how is not intuitively obvious.
And, as long as we know how to invoke it reliably and properly, we don't __need__ to understand how. (Though, being nerds, we often want to.) I agree: "Magic" is one of the best shorthands for "We can explain that later but for now let's assume this works".
Its magic because we know what it is doing, but the how is not intuitively obvious.