peritectic reaction

An isothermal, reversible reaction between two phases, a liquid and a solid, that results, on cooling of a binary, ternary, ... , $n$ system in one, two, ... ( $n − 1$ ) new solid phases. Synonymous with incongruent reaction.

Source:

PAC, 1994, 66, 577 (Definitions of terms relating to phase transitions of the solid state (IUPAC Recommendations 1994)) on page 588

peritectic reaction

Synonym: incongruent reaction