Frequent search covers area (5)
I believe the answer is:
haunt
'frequent' is the definition.
(thesaurus)
'search covers area' is the wordplay.
'search' becomes 'hunt' ('hunt' can be a synonym of 'search').
'covers' means one lot of letters goes inside another.
'area' becomes 'a' (maths abbreviation).
'hunt' enclosing 'a' is 'HAUNT'.
(Other definitions for haunt that I've seen before include "favourite spot" , "get spirits?" , "Unhat (anag.)" , "place regularly visited" , "Visit in spectral form" .)