solid solution

This term is a specialized technical expression used primarily in materials science, chemistry, and metallurgy. It describes a homogeneous mixture where the solute atoms are distributed within the solvent's crystal lattice without changing the overall structure of the phase. It is distinct from a mixture or a compound because the components are integrated at the atomic level.

In a professional or academic context, the term is often qualified as either substitutional, where solute atoms replace solvent atoms, or interstitial, where solute atoms fit into the gaps between solvent atoms. It is almost exclusively used in formal scientific discourse and is not used in casual conversation.