As in "2 cups sugar, divided"? How about "3 Tbsp butter, divided"? Or "1 Tbsp plus 1 cup skim milk, divided"?

Different recipe writers and different publishers use different conventions to express their recipes. They are trying for absolute consistency, so that you always know what to do and so that the recipe works the same for everyone who is likely to buy that cookbook or magazine. Some writers/publishers are better at it than others.

This is one convention used by some writers. It means – using our first example – that the recipe calls for 2 cups of sugar, but it is not all used at once. You may use a portion in the initial preparation and the remainder in a step further on in the recipe. Sometimes they tell you up front how to divide the ingredient (1 Tbsp plus 1 cup skim milk, divided); other times, they tell you total amount and only spring the specifics on you when you are working through the process ("Melt 1 Tbsp of butter in a frying pan…." "Add the remaining 2 Tbsp butter to the mixture….")

However it's done, the convention is meant to keep you from adding all the sugar at once, and to avoid listing sugar as an ingredient on two separate lines, where you might overlook one or come to the conclusion that it's a misprint.