No. "Pump[ing]" by buying something is entirely legal. And the price should come down just as much when you are trying to cash in, so the mechanism doesn't really work, or anyone with enough money could just do it repeatedly using whatever traded asset they want.

"Pump and dump" refers to promoting some investment by other means, usually spreading some false news.

> "Pump[ing]" by buying something is entirely legal.

I beg to differ. The Securities and Exchanges Act of 1934 criminalizes all sorts of things that are deemed market manipulation, and inflating the price of a security by false trading, i.e. selling it to yourself or a conspirator, is one of the very things it was created to prohibit.

It can be still pump and dump because rising price induces fomo.

Market manipulation, yes. Pump and dump is a subset of it.