◎

Symbol

 * 1)  calcium ("lime", Daltonian symbol)
 * Technically, this should be red: ◎ . May also be typeset ⊚| ⊚ or ⦾| ⦾, depending on which character matches the size of the other elements.

Etymology
Literally 二重丸, 'two times circle'. A doubling ○ for emphasis.

Symbol

 * 1) very good (better than ○)
 * 2)  city hall or other municipal building
 * This use may be formatted with a heavy outer ring: [[File:Japanese Map symbol (City Hall).svg]]