Dissatisfied means unhappy with something because it doesn't meet your expectations or needs. When you're dissatisfied with a meal at a restaurant, it might be cold, tasteless, or not what you ordered. When a teacher is dissatisfied with sloppy homework, the work falls short of the standards she expects.

The word suggests more than just a passing disappointment. Being dissatisfied means feeling genuinely let down because something you cared about didn't measure up. A customer dissatisfied with a broken toy might return it to the store. A coach dissatisfied with his team's effort during practice knows they can do better.

Notice the difference from being unsatisfied, which usually means still wanting more of something (like being unsatisfied after a small snack), while dissatisfied means being unhappy with the quality or nature of what you got. If you order a pizza and it arrives burnt and cold, you're dissatisfied. If you eat the whole delicious pizza but wish you had ordered two, you're unsatisfied.

People can also feel dissatisfied with themselves when they know they haven't given their best effort or lived up to their own standards. That kind of dissatisfaction can actually be useful: it's a signal that something needs to change, and that you can do better next time.