Most nasty blokes circling area in front of estate (7)
I believe the answer is:
meanest
'most nasty' is the definition.
('mean' can be similar in meaning to 'nasty')
'blokes circling area in front of estate' is the wordplay.
'blokes' becomes 'men' (I've seen this in another clue).
'circling' means one lot of letters goes inside another (circling can mean going around or containing).
'area' becomes 'a' (maths abbreviation).
'in front of' is a charade indicator (letters next to each other).
'estate' becomes 'est' (I've seen this in other clues).
'men' placed around 'a' is 'mean'.
'mean'+'est'='MEANEST'
(Other definitions for meanest that I've seen before include "of least value" , "Most cruel" , "Art expressing" , "Most unpleasant" , "Most stingy and least generous" .)