Evacuation, in animal economy, is the act of diminishing, attenuating, or discharging the humours.

The dueevacuations of the body, and its proper nourishment, are equally necessary; and it is an object of the utmost importance, that nothing remain in the constitution which should be discharged; and that whatever is conducive to its preservation, may not be uselessly-wasted. If the evacuations be disordered, the most rigid adherence to dietetic rules will not contribute to the continuance, or restoration of health ; these rules, however, may often be dispensed with, provided the evacuations be regular.

It is not only the noxious, or corrupt matter, which is removed by this process, but also the useful fluids, if they abound, such as the milk, blood, etc. to which subjects we refer, and likewise to the articles Ear, Nose, Urine,'etc. .