mole

https://doi.org/10.1351/goldbook.M03980
SI base unit for the @A00297@ (symbol: \(\text{mol}\)). The mole is the @A00297@ of a system which contains as many elementary entities as there are atoms in 0.012 @K03391@ of carbon-12. When the mole is used, the elementary entities must be specified and may be atoms, molecules, ions, electrons, other particles, or specified groups of such particles.
Sources:
Green Book, 2nd ed., p. 70 [Terms] [Book]
PAC, 1996, 68, 957. (Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)) on page 983 [Terms] [Paper]