By the broadest definition, a body cavity is any fluid-filled space in a multicellular organism, other than those of vessels (such as blood vessels and lymph vessels). However, the term usually refers to the space located between an animal’s outer covering (epidermis), and the outer lining of the gut cavity, where internal organs develop. "The human body cavity", normally refers to the ventral body cavity, because it is by far the largest one in volume.
Grouping
The type of body cavity places an organism into one of three groups:
* Coelomates or Coelomata (also known as eucoelomates — "...