Altcoin
Any cryptocurrency other than Bitcoin — from major networks like Ethereum to small experimental tokens.
An altcoin (“alternative coin”) is any cryptocurrency that is not Bitcoin. The term covers everything from Ethereum — a platform running thousands of applications — to tiny experimental tokens with no track record.
Altcoins generally carry higher risk and higher volatility than Bitcoin: many serve niche purposes, some iterate on Bitcoin’s design with faster or cheaper transactions, and a large share fail entirely. When traders say “altcoin season”, they mean a market phase where altcoins outperform Bitcoin, often visible as a fall in Bitcoin’s market-cap dominance.