Stuff in vacuous policy papers is a wonder (7)
I believe the answer is:
pyramid
'a wonder' is the definition.
(the Great Pyramid of Giza is a wonder of the world)
'stuff in vacuous policy papers' is the wordplay.
'stuff' becomes 'ram' (ramming is a kind of stuffing**).
'in' indicates putting letters inside.
'vacuous' suggests removing the centre.
'papers' becomes 'id' (identification papers).
'policy' with its middle removed is 'py'.
'py'+'id'='pyid'
'ram' put inside 'pyid' is 'PYRAMID'.
'is' acts as a link.
(Other definitions for pyramid that I've seen before include "Type of polyhedron" , "Polyhedron, one face a polygon, the rest triangles with common vertex" , "Form of ancient Egyptian royal tomb" , "ancient monument" , "Egyptian landmark" .)