noun a treatise on the science.
2. geology ·noun the science which treats: (a) of the structure and mineral constitution of the globe; structural geology. (b) of its history as regards rocks, minerals, rivers, valleys, mountains, climates, life, ·etc.; historical geology. (c) of the causes and methods by which its structure, features, changes, and conditions have been produced; dynamical geology. ·see chart of the geological series.