Rave has two main meanings:

1. To speak or write with wild, uncontrolled enthusiasm or anger. When critics rave about a new book, they can't stop praising it with intense excitement. Your friend might rave about an incredible pizza they tried, going on and on about how amazing it was. People can also rave in anger, shouting without making much sense, though the enthusiastic meaning is more common today. A rave review in a newspaper means the reviewer loved something so much they wrote about it with excitement and passion.
2. A type of large dance party featuring electronic music, flashing lights, and energetic dancing that became popular in the 1980s and 1990s. Raves often lasted all night and attracted huge crowds. The word captures the intense, almost frenzied energy of these events. Today, the term also applies to similar electronic music concerts and festivals.

Both meanings share that sense of intense, uncontrolled energy, whether it's excitement pouring out in words or through dancing and music.