Surface display covers everything (7)
I believe the answer is:
shallow
'surface' is the definition.
(thesaurus)
'display covers everything' is the wordplay.
'display' becomes 'show' (synonyms).
'covers' is an insertion indicator.
'everything' becomes 'all' (all things).
'show' placed around 'all' is 'SHALLOW'.
(Other definitions for shallow that I've seen before include "justice" , "incapable of serious thought" , "Not profound" , "Without depth" , "Lacking depth" .)