Meaning
A white circle with a thin outline, the light partner of ⚫. It means white, empty or neutral, and on light screens it can look like an unselected option.
People use it for clean bullet lists, unselected choices next to 🔘, black-and-white stone games and anything white, from pearls to snow: “Pick one: 🔘 cash ⚪ card” In dark mode it stands out far more than on white backgrounds. Its square cousin is ⬜.