monotectoid reaction

A reaction in a system containing two solid solution phases, $Math - text$ and $Math - text$ in which $Math - text$ decomposes into $Math - text$ and a new phase $Math - text$ :

$Math - c$

Source:

PAC, 1994, 66, 577 (Definitions of terms relating to phase transitions of the solid state (IUPAC Recommendations 1994)) on page 586