Where does the phrase “hand over fist” come from and What does it mean?

At first, the phrase “hand over fist” was a nautical expression with a very lateral meaning , advancing the hands alternately, as in climbing a rope, hoisting a sail, or the like.

Then, still nautical, it acquired a figurative sense, advancing continuously, as if by pulling something toward one by a rope. Thus, in overtaking another vessel rapidly, one spoke of coming up with it “hand over hand.”

In America, early in the nineteenth century, this second meaning acquired a further extension, hauling in rapidly, as if by reeling in a fish; and, Americans being flippant, the second “hand” became “fist,” so that now we say of a friend that he is making money “hand over fist” when his fortunes are in the ascendency.