Dilation
Any passage or opening leading to the interior of the body is known as a meatus. The external opening through which urine passes out of the body is called the urinary meatus.
nephrostomy DanielCR w/h
Dilation
Well, your anus contains the anal sphincter which, technically, is an opening of the body. So I would probably say the answer you are looking for is a sphincter muscle. Otherwise known as circular muscles
expansion slots :D
thermal expansion
McDonalds opening stores in Russia.
If a body is heated and after heating the body if the expand in one dimension then it is called linear expansion
In the human body there is no "opening" that stores food.
Why are you looking for an opening?
An acrocoracoid is a dorsal expansion of the coracoid bone which completes the opening for the triosseal canal.