Solvolysis Definition:

A substitution reaction in which the solvent functions as the nucleophile.

Solvolysis Explained:

In the reaction there is usually an alkyl halide (an organic substrate containing a halogen) that acts as the electrophile and a solvent molecule that acts as the nucleophile. For example, a tertiary benzyl chloride will undergo the reaction in which water acts as both the solvent and the nucleophile.