Body cavity
![](/Images/godic/202502/02/Annelid_redone_w_white_background.svg2757.png")
![Picture of human body cavities — dorsal body cavity to the left and ventral body cavity to the right.](/Images/godic/202502/02/Scheme_body_cavities-en.svg2757.png")
A body cavity is any fluid-filled space in a multicellular organism other than those of vessels (such as blood vessels and lymph vessels). 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.