English artist’s epoch (3)
I believe the answer is:
era
'epoch' is the definition.
(I know that epoch can be written as era)
'english artist's' is the wordplay.
'english' becomes 'e' (abbreviation).
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'e'+'ra'='ERA'
(Other definitions for era that I've seen before include "US equality law" , "Important date" , "Important time" , "Special time" , "Long period of time" .)