A parameter that is not strictly for the statistical model (or data generating process), but a parameter for the statistical method. It could be a parameter for: a family of prior distributions, smoothing, a penalty in regularization methods, or an optimization algorithm.
A hyperparameter is a parameter that is not strictly for the statistical model (or data-generating process), but a parameter for the statistical method. It could be a parameter for: a family of prior distributions, smoothing, a penalty in regularization methods, or an optimization algorithm.