Shill is a term in the crypto community that refers to the activity of promoting a crypto asset or project. The person who does it is called a Shiller. There are open shills and hidden shills. An open shill can provide free information. They will usually say: “I want to shill you a good project”.
On the other hand, hidden Shiller has hidden agenda to promote a project so people will buy it. This kind of shill usually exaggerates positive, unproven facts. For example, “a blockchain with a high TPS and can solve industry problems for $6 million”.