English

interreaction

From inter- + reaction.

Proto-Indo-European *h₁én ‘in’

Proto-Indo-European *h₁entér ‘between’

Proto-Italic *n̥ter ‘between’

Latin inter ‘between’

Proto-Indo-European *h₂eǵ- ‘to drive’

…

Latin reagō ‘to act upon again; to react’

Latin reāctiō ‘reaction’

Old French reaction

Middle English reaccion

Today it means

noun The reaction between two or more compounds, elements, etc.

Language periods are conventional ranges, not dates for this word.

Etymograph / interreaction