Biological symbol
The symbol for the planet Venus is the sign also used in biology for the female sex. It is a stylized representation of the goddess Venus's hand-mirror or an abstract symbol for the goddess: a circle with a small equilateral cross underneath (Unicode: ♀). The Venus symbol also represented femininity, and in ancient alchemy stood for copper. Alchemists constructed the symbol from a circle (representing spirit) above an equilateral cross (representing matter).