The circle and arrow represent the shield and spear, respectively, of the Ancient Roman god of war Mars.
1961 August 17, New Scientist, volume 11, number 248 (in English), Reed Business Information, ISSN 0262-4079, page 413:
- In his Mantissa Plantarum (1767) and Mantissa Plantarum altera (1771), [Linnaeus] regularly used ♂, ♀ and ☿ for male, female and hermaphrodite flowers respectively.
- 1990, Charles S. Churcher, “Cranial Appendages of Giraffoidea”, George A. Bubenik, Anthony B. Bubenik, Horns, Pronghorns, and Antlers: Evolution, Morphology, Physiology, and Social Significance, New York: Springer-Verlag, →ISBN, chapter 1.5, page 183:
- Figure 2. Ossicones, secondary ossification, and sinuses of Giraffa: A Lateral aspect of skull showing courses of veins, areas of dense ossification (heavily stippled) and lesser secondary ossification (lightly stippled), and outlines of skull roofs of male (♂) and female (♀) adults. (After Spinage 1968b.)
2015 July 6, Andy Burns, “Re: C4 last leg”, in uk.tech.broadcast, Usenet (in English):
I was quite surprised that a few of my friends found the male ♂ (mars) and female ♀ (venus) symbols on toilets in pubs/bars confusing ...
- (botany, of a flower) Staminate.
- (astronomy, astrology) Mars.
- (alchemy) Iron dominated by Mars.
- ^ “Solar System Symbols”, in Solar System Exploration, NASA and the Planetary Institute, January 30, 2018, retrieved November 3, 2019: “The symbol for Neptune is the trident (long three-pronged fork or weapon) of Neptune, god of the sea.”