Englishman accepted hard worker's illusion (7)
I believe the answer is:
phantom
'illusion' is the definition.
(I know that phantom is a type of illusion)
'englishman accepted hard worker's' is the wordplay.
'englishman' becomes 'pom' (pom is an Australian term for an English person).
'accepted' means one lot of letters goes inside another.
'hard' becomes 'h' (abbreviation used in pencil classifications).
'worker' becomes 'ant' (worker is a type of ant).
'h'+'ant'='hant'
'pom' placed around 'hant' is 'PHANTOM'.
(Other definitions for phantom that I've seen before include "Spirit" , "Ballet-dancing costume" , "shadow of his former self?" , "Illusion (at the opera?)" , "Blush" .)