A coin pair with $BNB refers to trading pairs on cryptocurrency exchanges where Binance Coin (BNB) is one of the two currencies involved in the trade. Binance Coin is the native cryptocurrency of the Binance exchange and is widely used for trading fee discounts, transaction fees, and other utilities within the Binance ecosystem. Common coin pairs with BNB include BNB/USDT, BNB/BTC, and BNB/ETH, where traders can exchange BNB for other cryptocurrencies or stablecoins like USDT. These pairs offer liquidity and flexibility for users who want to trade BNB against various other digital assets. Trading in BNB pairs can also help leverage its use for reducing fees or accessing specific Binance services, making it a key part of the Binance exchange ecosystem.