1) A quantity in an equation which must be specified beside the independent variables to obtain the solution for the dependent variables.

2) A quantity which is constant under a given set of conditions, but may be different under other conditions.

Eionet; EEA (2021) GEMET – General Multilingual Environmental Thesaurus. Available at: https://www.eionet.europa.eu/gemet/en/groups/ (Accessed: 10 July 2023).