An alchemical sign for sal ammoniacus, or ammonium salt. It is synonymous with
e.g. in Group 41:b, and with
in Group 3. The other
synonyms can be found via the Word Index.
Sometimes is used for the planet Uranus.
This sign is also a letter in the Cyrillic alphabet used by some Slavic people like Russians and Serbs.
It is also a symbol for an Italian sect founded by David Lazzaretti at the end of the nineteenth century.
Lastly, some ufologists claim it is a symbol for a planet in another sun system, called Ummo, some of whose inhabitants they say have been in contact with humans on our planet.