- (astronomy) Mercury.
- (alchemy) Mercury (quicksilver) dominated by Mercury.
- 1961 August 17, New Scientist, volume 11, number 248, 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.
- The genders are typically represented by symbols derived from the planets. The female (Venus) and male (Mars) symbols (shown below) are commonly known and used.
- Venus ♀ Mars ♂ Mercury ☿
- As not everyone believes that they fit into either the male or female gender role regardless of their biological genetic sex, they tend to refer to themselves as the third category, intersex, intergender or transgender (see Mercury symbol above).
- (entomology) worker
- 1903, C. T. Bingham, Hymenoptera.—Vol. II. Ants and Cuckoo-wasps (The Fauna of British India, Including Ceylon and Burma), London: Taylor and Francis, page v:
- Ants like the honey-bees and one section of the wasps, are social insects with, in any well-established nest or community, three distinct forms—the perfect and fertile female (♀) the male (♂), and the so-called neuter or worker (☿), which is merely an undeveloped female.