oxidation number

In English is largely synonymous with oxidation state, and may be preferred when the value represents a mere parameter or number rather than being related to chemical systematics or a state of the atom in a compound. Etymologically, it stems from the no-longer-used term Stock number (oxidation number of a central atom; the charge it would bear if all the ligands were removed along with the electron pairs that were shared with the central atom) and the likewise obsolete term Ewens–Bassett number (ion charge).
PAC, 2014, 86, 1017. 'Toward a Comprehensive Definition of Oxidation State' on page 1020-1021 (https://doi.org/10.1515/pac-2013-0505)
PAC, 2016, 88, 831. 'Comprehensive definition of oxidation state' on page 832 (https://doi.org/10.1515/pac-2015-1204)