boil down

To reduce in volume by boiling.

“He boiled the soup down so it wouldn't be so weak.”

To become reduced (to the most central elements or ingredients: to the essence, core or implication for action).

“So what this boils down to is that you still owe me that fifty bucks.”

To reduce (to the most central elements or ingredients: to the essence, core or implication for action).

“My dissertation is 342 pages long, and I'm required to boil it down to a one-page abstract?!”