compression factor, \(Z\)

https://doi.org/10.1351/goldbook.C01216
Product of pressure and molar volume divided by the gas constant and thermodynamic temperature. For an ideal gas it is equal to 1.
Source:
Green Book, 2nd ed., p. 49 (https://dev.goldbook.iupac.org/files/pdf/green_book_2ed.pdf)