be the beginning of the end

1. To be the start of a decline. We didn't realize it at the time, but not having any interest in spending Valentine's Day together was the beginning of the end for our relationship—we broke up a month later. Apparently, these symptoms are usually the beginning of the end for patients who have this illness. I can't believe she didn't get more money for her house. I really hope this isn't the beginning of the end for decent housing prices in our neighborhood.

2. To be the first in a series of closing events. Senior prom is really the beginning of the end—graduation isn't that far away anymore. A: "I can't believe my baby is 16! Is this the beginning of the end? Driving, then college, then marriage?" B: "Whoa, Mom, relax!" A: "It's our last first day of school! It's the beginning of the end!" B: "I guess, but we still have our entire senior year ahead of us."