Quixotic comes from Don Quixote, the famous character created by Miguel de Cervantes. Don Quixote is noble, imaginative, and determined, but he often mistakes fantasy for reality. Because of that, quixotic came to describe ideas or actions that are admirable in spirit but unlikely to work in real life.
Today, the word usually suggests a mix of good intentions and impractical thinking. It is often used for plans, causes, or people.
- A quixotic plan: trying to end all war by next week.
- A quixotic mission: attempting to fix every problem in one day.
- A quixotic person: someone brave and idealistic, but not realistic about the obstacles.
This word is not exactly the same as optimistic. An optimistic person hopes things will go well. A quixotic person may chase a noble goal in a way that ignores reality. That contrast is the key meaning.