⊙

Description
A dot centered inside a circle.

Symbol

 * 1)  A vector pointing out of the page.
 * 2)  The Hadamard product between two matrices.
 * 3)  ISO 2047 symbol for Shift In.
 * 4)  XNOR gate.
 * 5)  hydrogen (Daltonian symbol)
 * Technically, this should be red: ⊙ . May also be typeset ☉| ☉.

Antonyms

 * (vector pointing into the page)