critical solution point

Synonym: consolute point
https://doi.org/10.1351/goldbook.C01400
The point, with coordinates @C01401@ and critical composition, on a temperature-composition phase diagram at which the distinction between co-existent phases vanishes. In solid-solid, solid-liquid and liquid-liquid systems both upper and lower @C01401@ and corresponding @C01399@ can occur. Synonymous with consolute point.
Source:
PAC, 1994, 66, 577. (Definitions of terms relating to phase transitions of the solid state (IUPAC Recommendations 1994)) on page 580 [Terms] [Paper]