Is milk a colloidal solution or compound?

Explanation of the milk is a colloidal solution: Colloid is a mixture in which tiny particles of one component are scattered in a dispersion medium of another substance. Particles range in size from ${10}^{-9}\mathrm{to}{10}^{-6}\mathrm{m}.$

Milk is a water-fat emulsion of milk fat (liquid phase). An emulsion is a colloid comprised of two or even more heterogeneous liquid kinds in which the dispersion of the different liquid types is concentrated in one of them. Thus milk is an example of an emulsion of a colloid in which both the dispersed phase and dispersion medium are in the liquid.

In conclusion, thus milk is a colloidal solution, not a compound.