peritectic reaction

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