Element Symbol Definition in Chemistry

Chemistry Glossary Definition of Element Symbol

Periodic table of elements
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In chemistry, an element symbol sually refers to the one- or two-letter abbreviation for a chemical element, though the term can be applied to the alchemical symbols also.

Key Takeaways: Element Symbol Definition

  • An element symbol is a one or two letter abbreviation for a chemical element name.
  • When a symbol consists of two letters, the first letter is always capitalized, while the second letter is lowercase.
  • Element symbols may also refer to alchemy symbols for the elements or for the symbols used to describe isotopes.

Element Symbol Examples

Examples of modern element symbols include H for hydrogen, He for helium, and Ca for calcium. The first letter of an element symbol is capitalized, while the second letter is lowercase.

An example of a deprecated element symbol is Cb for columbium, which was the former name of the element niobium. However, some elements retain their old symbols when they change names. For example, Ag is the element symbol for silver, which was once called argentum.


  • Fontani, Marco; Costa, Mariagrazia; Orna, Mary Virginia (2014). The Lost Elements: The Periodic Table's Shadow Side. Oxford University Press. ISBN 9780199383344.
  • Leal, João P. (2013). "The Forgotten Names of Chemical Elements". Foundations of Science. 19: 175–183. doi:10.1007/s10699-013-9326-y
  • Wieser, Michael E.; et al. (2013). "Atomic weights of the elements 2011 (IUPAC Technical Report)". Pure Appl. Chem. IUPAC. 85 (5): 1047–1078. doi:10.1351/PAC-REP-13-03-02