Meaning
A small disc inside a square case, resembling a MiniDisc or a similar storage disk. It stands for data storage and recorded media from the era of physical formats.
It mostly appears in retro tech talk, mixtape nostalgia or posts about backing up files: “Found my old 💽 collection while cleaning, so many forgotten songs.” Because it looks close to 💾 and 💿, people often use it loosely for any old disk.