Definition Dissection is the dismembering of an animal or human body chiefly for instructional purposes. Although the Latin word sectio referred more broadly to any manual operation of opening up of bodies in order both to demonstrate its structure and to search for the causes of death, in the early modern epoch, its derivative "dissection" progressively came to denote the procedures used for the teaching of anatomy and the means to investigate physiology. At the end of the eighteenth century, standard dictionaries and encyclopedias, like Ephraim Chambers' Cyclopaedia: or, An Universal Dictionary of Arts and Sciences (1738 edition), defined "dissection" as "the operation of cutting and dividing the parts of an animal body with a knife, scissors, etc., in order to see and consider each of them apart," while "autopsy" was mainly used in reference to the inspection of cadavers for legal or medical purposes.