A pessimist is someone who tends to expect bad outcomes and focus on what might go wrong. When a pessimist looks at a situation, they're more likely to see problems than possibilities. If dark clouds appear before a baseball game, a pessimist assumes it will rain and ruin everything, while an optimist hopes the clouds will pass.

The word comes from the Latin pessimus, meaning “worst.” A pessimist often imagines the worst-case scenario. Before a school presentation, a pessimist worries they'll forget their lines, drop their notes, and embarrass themselves. Before trying out for the play, they convince themselves they won't get a part.

Being pessimistic is different from being realistic or careful. A realistic person considers both good and bad possibilities. A pessimist dwells mainly on the negative ones, which can make them miss opportunities or give up before trying. If you're working on a difficult math problem and your partner keeps saying, “This is impossible, we'll never figure it out,” that's pessimism talking.

The opposite of a pessimist is an optimist, someone who expects good things to happen. Most people fall somewhere in between, sometimes hopeful and sometimes worried. While it's wise to prepare for challenges, persistent pessimism can become a habit that holds you back from attempting things you might actually accomplish.