Hello, on #btcmap we use that tag to indicate that this payment method is used in businesses. It’s uncommon, but it is used. Here’s a brief explanation of what Liquid is in Bitcoin; I hope it helps. If you have any other questions, feel free to contact me.

"Bitcoin Liquid is a federated sidechain built on top of Bitcoin that enables faster, confidential, and lower‑fee transactions for exchanges, traders, and institutions. It also supports the issuance of digital assets and tokenized securities, allowing users to move value securely between the main Bitcoin blockchain and the Liquid network"

