critical point

https://doi.org/10.1351/goldbook.C01396
The temperature and pressure at which the liquid and vapour intensive properties (density, @H02753@, etc.) become equal. It is the highest temperature (@C01402@) and pressure (@C01397@) at which both a gaseous and a liquid phase of a given compound can coexist.
Sources:
PAC, 1990, 62, 2167. (Glossary of atmospheric chemistry terms (Recommendations 1990)) on page 2183 [Terms] [Paper]
PAC, 1993, 65, 2397. (Nomenclature for supercritical fluid chromatography and extraction (IUPAC Recommendations 1993)) on page 2399 [Terms] [Paper]