Mantle
a kind of cloak or loose garment to be worn over other garments.
In heraldry the name is given to the MANTUA cloak or mantle which is often represented behind the escutcheon. In zoölogy the mantle is the soft skin or integument of molluscous animals, otherwise known as the pallium. This structure secretes the shell when present, and where the shell is absent the mantle forms an investing sac or integument in which the viscera and other organs are contained and protected.