A permabull is someone who always sees developments in the market in an optimistic light and therefore has no eye for negative developments. A permabull continues to believe that his positions will be worth more in the future than they are now. When the entire crypto market crashed in 2018, there were many people who continued to believe in better times (and were eventually proven right). Here you can find the famous bagholder bingo card for crypto Permabulls: https://www.reddit.com/r/CryptoCurr