Seems a paper's gone astray (7)
I believe the answer is:
appears
'seems' is the definition.
('appear' can be a synonym of 'seem')
'a paper's gone astray' is the wordplay.
'gone astray' indicates an anagram (I've seen this in other clues).
'papers' with letters rearranged gives 'ppears'.
'a'+'ppears'='APPEARS'
(Other definitions for appears that I've seen before include "Looks like" , "is exhibited" , "Comes into sight" , "Seems" , "Comes into view" .)