Phys`i*ol"o*gy (?), n.; pl. Physiologies (#). [L. physiologia, Gr. ?; fy`sis nature + ? discourse: cf. F. physiologie.] 1. The science which treats of the phenomena of living organisms; the study of the processes incidental to, and characteristic of, life.

☞ It is divided into animal and vegetable physiology, dealing with animal and vegetable life respectively. When applied especially to a study of the functions of the organs and tissues in man, it is called human physiology.

2. A treatise on physiology.

Mental physiology, the science of the functions and phenomena of the mind, as distinguished from a philosophical explanation of the same.