MATERIA MEDICA, derived from two _Latin_ words signifying medical
material, the science which treats with medicine, their source or
origin, their derivatives, physical and chemical properties, their
method of preparation and administration, their dose, physiological and
toxicological effects.
THERAPEUTICS, derived from the Greek, _Therapevo_, meaning to serve or
attend the sick, is that branch of knowledge which treats of the
application of all means--medical or otherwise--to the cure of disease
or relief of pain.
TOXICOLOGY, derived from the Greek _Toxikon_, a poison, is that branch
of knowledge which treats of the nature, actions, detection and
treatment of poisons.
A _medicine_ is an agent of animal, vegetable, or mineral origin used
for the cure of disease or relief of pain.
DRUG, derived from the Dutch, _Droog_, meaning dry, is now used
synonymously with medicine although originally referring to an herb or
dried medical plant.