A Bitcoiner is that buddy who can't stop talking about Bitcoin. Since the early 2010s, many Bitcoiners have been HODLing their coins. Most likely, your Bitcoiner buddy will be checking their phone to keep you up to speed on the current price of Bitcoin, either ecstatic about their recent profits or crushed by the latest downturn, fearful that their life savings will be wiped out.
Despite Bitcoin's volatility, a Bitcoiner sees a future where Bitcoin continues to dominate the cryptocurrency market capitalization. Some utopian Bitcoiners may even feel that cryptocurrency can transform the world’s political and financial systems.