Body or corps is a generic term referring to a group, a unity. In biology it refers to the concrete structure of a human being. In physics it represents an entity. In the army, a corps is a unity. It may also refer to the association of several professions of the same category such as medical corps for instance. In astronomy it designs any material present in the universe (celestial body)...

Hence, a body is a block composed with several elements connected one to another. In this way, if a human being has various limbs and organs, the whole constitutes the body. In a restrictive manner, the body is constituted by the trunk and the pelvis.
Unlike the biological term that defines the body as the human organism as a whole, the informal language links the body to death in so far as it may design lifeless being, a cadaver.

The cult of body is very important in our current societies, but did you know that some common practices were born some millenniums ago? Thus Egyptians used to make themselves up (using lead), roots of aesthetics were found in Ancient Greece, and tattoos on prehistorical men.