Margin trading in cryptocurrency is a practice where an investor borrows funds from a broker or an exchange to trade a larger position than their initial capital allows. This strategy allows traders to potentially amplify their profits, but it also increases the risk of significant losses, as losses are also magnified in the same way. Margin trading involves the use of leverage, which means that traders can control a larger position with a smaller amount of capital. It is important to note that margin trading can be highly risky and should only be undertaken by experienced traders who understand the potential risks involved.