gender symbol Mars symbol A depiction of a circle with an arrow emerging from it, pointing at an angle to the upper right. As astrological symbol it represents the planet Mars. It is also the old and obsolete symbol for iron in alchemy. In zoology and botany, it is used to represent the male sex (alongside the astrological symbol for Venus representing the female sex), following a convention introduced by Linnaeus in the 1750s. Mars symbols Venus symbol