A letdown is the disappointing feeling you get when something doesn't live up to what you hoped or expected. If you've been looking forward to a school field trip for weeks, imagining all the exciting things you'll see and do, but then it gets canceled at the last minute, that sinking feeling in your stomach is a letdown. Or imagine finally getting to see a movie everyone's been raving about, only to find it boring and predictable. That's a letdown too.

The word captures that specific moment when reality falls short of anticipation. A letdown happens when there's a gap between what you thought would happen and what actually happens. When your favorite restaurant runs out of your go-to dish, when a highly anticipated game turns out to be glitchy and frustrating, or when a friend cancels plans you'd been excited about, you experience a letdown.

Sometimes people use the phrase let down as a verb, meaning to disappoint someone: “I don't want to let down my teammates by missing practice.” The weight of other people's expectations can feel heavy because nobody wants to be the reason someone else feels disappointed.