## Wikipedia - Pressure pressure, $$p$$

https://doi.org/10.1351/goldbook.P04819
Normal force acting on a surface divided by the area of that surface. For a mixture of gases the contribution by each @C01281@ is called the @P04420@ $$p_{i}=x_{i}\ p$$, where $$x_{i}$$ is the @A00296@ of the $$i$$th @C01281@ and $$p$$ is the total pressure.
Sources:
Green Book, 2nd ed., p. 12 [Terms] [Book]
PAC, 1996, 68, 957. (Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)) on page 987 [Terms] [Paper]