Nondegenerate gas
= Nondegenerate gas
A gas is nondegenerate when its occupation numbers are low enough that <quantum statistics> reduce to the <Maxwell-Boltzmann distribution>. A common criterion is $n\lambda_{\rm th}^3\ll1$, where $\lambda_{\rm th}$ is the thermal de Broglie wavelength.
For an <ideal gas>, this is the classical statistical regime; nondegeneracy alone does not assert the absence of interactions.