Definition of humoral theory in US English:

humoral theory


  • 1The theory that the balance and condition of the four humours, or (in later use) the body fluids generally, are responsible for states of health and disease; any theory of this nature (now historical).

  • 2Any theory attributing a physiological role to specific chemical substances in the body fluids; (Immunology) the theory that immunity, or a specific immunological phenomenon, is dependent upon the action of antibodies rather than cells.


Late 18th century.