<P> Antimatter atoms are denoted by a bar above the symbol for their matter counterpart, so e.g. H is the symbol for antihydrogen . </P> <P> The following is a list of symbols and names formerly used or suggested for elements, including symbols for placeholder names and names given by discredited claimants for discovery . </P> <Table> <Tr> <Th> Chemical symbol </Th> <Th> Name </Th> <Th> Atomic number </Th> <Th> Origin of symbol </Th> <Th> Why not used </Th> <Th> Refs </Th> </Tr> <Tr> <Td> </Td> <Td> Argon </Td> <Td> 18 </Td> <Td> A used for Argon until 1957 . Current symbol is Ar . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ab </Td> <Td> Alabamine </Td> <Td> 85 </Td> <Td> Discredited claim to discovery of astatine . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ad </Td> <Td> Aldebaranium </Td> <Td> 70 </Td> <Td> Former name for ytterbium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Am </Td> <Td> Alabamium </Td> <Td> 85 </Td> <Td> Discredited claim to discovery of astatine . The symbol is now used for americium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> An </Td> <Td> Athenium </Td> <Td> 99 </Td> <Td> Proposed name for einsteinium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ao </Td> <Td> Ausonium </Td> <Td> 93 </Td> <Td> Discredited claim to discovery of neptunium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Az </Td> <Td> Azote </Td> <Td> 7 </Td> <Td> Former name for nitrogen . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Bo </Td> <Td> Boron </Td> <Td> 5 </Td> <Td> Current symbol is B . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Bv </Td> <Td> Brevium </Td> <Td> 91 </Td> <Td> Former name for protactinium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Bz </Td> <Td> Berzelium </Td> <Td> </Td> <Td> Baskerville wrongly believed berzelium to be a new element . Was actually thorium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Cb </Td> <Td> Columbium </Td> <Td> 41 </Td> <Td> Former name for niobium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ch </Td> <Td> Chromium </Td> <Td> 24 </Td> <Td> Current symbol is Cr . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Cl </Td> <Td> Columbium </Td> <Td> 41 </Td> <Td> Former name for niobium . The symbol is now used for chlorine . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Cn </Td> <Td> Carolinium </Td> <Td> </Td> <Td> Baskerville wrongly believed carolinium to be a new element . Was actually thorium . The symbol is now used for copernicium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Cp </Td> <Td> Cassiopeium </Td> <Td> 71 </Td> <Td> Former name for lutetium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Cp </Td> <Td> Copernicium </Td> <Td> 112 </Td> <Td> Current symbol is Cn . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ct </Td> <Td> Celtium </Td> <Td> 72 </Td> <Td> Discredited claim to discovery of hafnium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ct </Td> <Td> Centurium </Td> <Td> 100 </Td> <Td> Proposed name for fermium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> </Td> <Td> Didymium </Td> <Td> </Td> <Td> Mixture of the elements praseodymium and neodymium . Mosander wrongly believed didymium to be an element . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Da </Td> <Td> Davyum </Td> <Td> 43 </Td> <Td> Discredited claim to discovery of technetium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Db </Td> <Td> Dubnium </Td> <Td> 104 </Td> <Td> Proposed name for rutherfordium . The symbol and name were instead used for element 105 . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Di </Td> <Td> Didymium </Td> <Td> </Td> <Td> Mixture of the elements praseodymium and neodymium . Mosander wrongly believed didymium to be an element . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ds </Td> <Td> Dysprosium </Td> <Td> 66 </Td> <Td> Current symbol is Dy . The symbol is now used for darmstadtium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> </Td> <Td> Einsteinium </Td> <Td> 99 </Td> <Td> Current symbol is Es . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> </Td> <Td> Erbium </Td> <Td> 68 </Td> <Td> Current symbol is Er . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ea </Td> <Td> Ekaaluminium </Td> <Td> 31 </Td> <Td> Name given by Mendeleev to an as of then undiscovered element . When discovered, gallium closely matched the prediction . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Eb </Td> <Td> Ekaboron </Td> <Td> 21 </Td> <Td> Name given by Mendeleev to an as of then undiscovered element . When discovered, scandium closely matched the prediction . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> El </Td> <Td> Ekaaluminium </Td> <Td> 31 </Td> <Td> Name given by Mendeleev to an as of then undiscovered element . When discovered, gallium closely matched the prediction . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Em </Td> <Td> Ekamanganese </Td> <Td> 43 </Td> <Td> Name given by Mendeleev to an as of then undiscovered element . When discovered, technetium closely matched the prediction . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Em </Td> <Td> Emanation </Td> <Td> 86 </Td> <Td> Also called "radium emanation", the name was originally given by Friedrich Ernst Dorn in 1900 . In 1923, this element officially became radon (the name given at one time to Rn, an isotope identified in the decay chain of radium). </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Em </Td> <Td> Emanium </Td> <Td> 89 </Td> <Td> Alternate name formerly proposed for actinium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Es </Td> <Td> Ekasilicon </Td> <Td> 32 </Td> <Td> Name given by Mendeleev to an as of then undiscovered element . When discovered, germanium closely matched the prediction . The symbol is now used for einsteinium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Es </Td> <Td> Esperium </Td> <Td> 94 </Td> <Td> Discredited claim to discovery of plutonium . The symbol is now used for einsteinium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Fa </Td> <Td> Francium </Td> <Td> 87 </Td> <Td> Current symbol is Fr . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Fl </Td> <Td> Florentium </Td> <Td> 61 </Td> <Td> Discredited claim to discovery of promethium . The symbol is now used for flerovium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Fl </Td> <Td> Fluorine </Td> <Td> 9 </Td> <Td> Current symbol is F. The symbol is now used for flerovium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Fr </Td> <Td> Florentium </Td> <Td> 61 </Td> <Td> Discredited claim to discovery of promethium . The symbol is now used for francium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> </Td> <Td> Glucinium </Td> <Td> </Td> <Td> Former name for beryllium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Gl </Td> <Td> Glucinium </Td> <Td> </Td> <Td> Former name for beryllium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ha </Td> <Td> Hahnium </Td> <Td> 105 </Td> <Td> Proposed name for dubnium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Hn </Td> <Td> Hahnium </Td> <Td> 108 </Td> <Td> Proposed name for hassium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Hv </Td> <Td> Helvetium </Td> <Td> 85 </Td> <Td> Discredited claim to discovery of astatine . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Hy </Td> <Td> Mercury </Td> <Td> 80 </Td> <Td> Hy from the Greek hydrargyrum for "liquid silver". Current symbol is Hg . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> </Td> <Td> Iridium </Td> <Td> 77 </Td> <Td> Current symbol is Ir . The symbol is now used for iodine . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Il </Td> <Td> Illinium </Td> <Td> 61 </Td> <Td> Discredited claim to discovery of promethium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> J </Td> <Td> Jodium </Td> <Td> 53 </Td> <Td> Former name for iodine . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Jg </Td> <Td> Jargonium </Td> <Td> 72 </Td> <Td> Discredited claim to discovery of hafnium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Jl </Td> <Td> Joliotium </Td> <Td> 105 </Td> <Td> Proposed name for dubnium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ka </Td> <Td> Potassium </Td> <Td> 19 </Td> <Td> Current symbol is K . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ku </Td> <Td> Kurchatovium </Td> <Td> 104 </Td> <Td> Proposed name for rutherfordium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> </Td> <Td> Lithium </Td> <Td> </Td> <Td> Current symbol is Li . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Lw </Td> <Td> Lawrencium </Td> <Td> 103 </Td> <Td> Current symbol is Lr . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> </Td> <Td> Muriaticum </Td> <Td> 17 </Td> <Td> Former name for chlorine . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ma </Td> <Td> Manganese </Td> <Td> 25 </Td> <Td> Current symbol is Mn . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ma </Td> <Td> Masurium </Td> <Td> 43 </Td> <Td> Disputed claim to discovery of technetium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Md </Td> <Td> Mendelevium </Td> <Td> 97 </Td> <Td> Proposed name for berkelium . The symbol and name were later used for element 101 . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ml </Td> <Td> Moldavium </Td> <Td> 87 </Td> <Td> Discredited claim to discovery of francium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ms </Td> <Td> Magnesium </Td> <Td> 12 </Td> <Td> Current symbol is Mg . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ms </Td> <Td> Masrium </Td> <Td> 88 </Td> <Td> Discredited claim of discovery of radium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ms </Td> <Td> Masurium </Td> <Td> 43 </Td> <Td> Disputed claim to discovery of technetium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Mv </Td> <Td> Mendelevium </Td> <Td> 101 </Td> <Td> Current symbol is Md . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ng </Td> <Td> Norwegium </Td> <Td> 72 </Td> <Td> Discredited claim to discovery of hafnium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> No </Td> <Td> Norium </Td> <Td> 72 </Td> <Td> Discredited claim to discovery of hafnium . The symbol is now used for nobelium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Np </Td> <Td> Nipponium </Td> <Td> 43 </Td> <Td> Discredited claim to discovery of technetium . The symbol is now used for neptunium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ns </Td> <Td> Nielsbohrium </Td> <Td> 105 </Td> <Td> Proposed name for dubnium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ns </Td> <Td> Nielsbohrium </Td> <Td> 107 </Td> <Td> Proposed name for bohrium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Nt </Td> <Td> Niton </Td> <Td> 86 </Td> <Td> Former name for radon . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ny </Td> <Td> Neoytterbium </Td> <Td> 70 </Td> <Td> Former name for ytterbium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> </Td> <Td> Lead </Td> <Td> 82 </Td> <Td> Current symbol is Pb . The symbol is now used for phosphorus . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Pa </Td> <Td> Palladium </Td> <Td> 46 </Td> <Td> Current symbol is Pd . The symbol is now used for protactinium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Pe </Td> <Td> Pelopium </Td> <Td> 41 </Td> <Td> Former name for niobium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Pl </Td> <Td> Palladium </Td> <Td> 46 </Td> <Td> Current symbol is Pd . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Po </Td> <Td> Potassium </Td> <Td> 19 </Td> <Td> Current symbol is K . The symbol is now used for polonium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> </Td> <Td> Rhodium </Td> <Td> 45 </Td> <Td> Current symbol is Rh . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Rd </Td> <Td> Radium </Td> <Td> 88 </Td> <Td> Current symbol is Ra . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Rf </Td> <Td> Rutherfordium </Td> <Td> 106 </Td> <Td> Proposed name for seaborgium . The symbol and name were instead used for element 104 . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ro </Td> <Td> Rhodium </Td> <Td> 45 </Td> <Td> Current symbol is Rh . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Sa </Td> <Td> Samarium </Td> <Td> 62 </Td> <Td> Current symbol is Sm . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> So </Td> <Td> Sodium </Td> <Td> 11 </Td> <Td> Current symbol is Na . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> St </Td> <Td> Antimony </Td> <Td> 51 </Td> <Td> Current symbol is Sb . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> St </Td> <Td> Tin </Td> <Td> 50 </Td> <Td> Current symbol is Sn . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Tn </Td> <Td> Tungsten </Td> <Td> 74 </Td> <Td> Current symbol is W . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Tr </Td> <Td> Terbium </Td> <Td> 65 </Td> <Td> Current symbol is Tb . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Tu </Td> <Td> Thulium </Td> <Td> 69 </Td> <Td> Current symbol is Tm . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Tu </Td> <Td> Tungsten </Td> <Td> 74 </Td> <Td> Current symbol is W . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Unb </Td> <Td> Unnilbium </Td> <Td> 102 </Td> <Td> Temporary name given to nobelium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Une </Td> <Td> Unnilennium </Td> <Td> 109 </Td> <Td> Temporary name given to meitnerium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Unh </Td> <Td> Unnilhexium </Td> <Td> 106 </Td> <Td> Temporary name given to seaborgium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Uno </Td> <Td> Unniloctium </Td> <Td> 108 </Td> <Td> Temporary name given to hassium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Unp </Td> <Td> Unnilpentium </Td> <Td> 105 </Td> <Td> Temporary name given to dubnium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Unq </Td> <Td> Unnilquadium </Td> <Td> 104 </Td> <Td> Temporary name given to rutherfordium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Uns </Td> <Td> Unnilseptium </Td> <Td> 107 </Td> <Td> Temporary name given to bohrium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Unt </Td> <Td> Unniltrium </Td> <Td> 103 </Td> <Td> Temporary name given to lawrencium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Unu </Td> <Td> Unnilunium </Td> <Td> 101 </Td> <Td> Temporary name given to mendelevium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Uub </Td> <Td> Ununbium </Td> <Td> 112 </Td> <Td> Temporary name given to copernicium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Uuh </Td> <Td> Ununhexium </Td> <Td> 116 </Td> <Td> Temporary name given to livermorium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Uun </Td> <Td> Ununnilium </Td> <Td> 110 </Td> <Td> Temporary name given to darmstadtium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Uuo </Td> <Td> Ununoctium </Td> <Td> 118 </Td> <Td> Temporary name given to oganesson until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Uup </Td> <Td> Ununpentium </Td> <Td> 115 </Td> <Td> Temporary name given to moscovium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Uuq </Td> <Td> Ununquadium </Td> <Td> 114 </Td> <Td> Temporary name given to flerovium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Uus </Td> <Td> Ununseptium </Td> <Td> 117 </Td> <Td> Temporary name given to tennessine until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Uut </Td> <Td> Ununtrium </Td> <Td> 113 </Td> <Td> Temporary name given to nihonium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Uuu </Td> <Td> Unununium </Td> <Td> 111 </Td> <Td> Temporary name given to roentgenium until it was permanently named by IUPAC . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Ur </Td> <Td> Uranium </Td> <Td> 92 </Td> <Td> Current symbol is U . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Vi </Td> <Td> Virginium </Td> <Td> 87 </Td> <Td> Discredited claim to discovery of francium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Vm </Td> <Td> Virginium </Td> <Td> 87 </Td> <Td> Discredited claim to discovery of francium . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Va </Td> <Td> Vanadium </Td> <Td> 23 </Td> <Td> Current symbol is V . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Wo </Td> <Td> Tungsten </Td> <Td> 74 </Td> <Td> Current symbol is W . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> X </Td> <Td> Xenon </Td> <Td> 54 </Td> <Td> Current symbol is Xe . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> Yt </Td> <Td> Yttrium </Td> <Td> 39 </Td> <Td> Current symbol is Y . </Td> <Td> </Td> <Td> </Td> </Tr> </Table> <Tr> <Th> Chemical symbol </Th> <Th> Name </Th> <Th> Atomic number </Th> <Th> Origin of symbol </Th> <Th> Why not used </Th> <Th> Refs </Th> </Tr>

What does the symbol a mean in chemistry
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