Revolutionary work introduced by English writer (5)
I believe the answer is:
eliot
'writer' is the definition.
(I've seen this before)
'revolutionary work introduced by english' is the wordplay.
'revolutionary' is a reversal indicator (letters revolve around).
'work' becomes 'toil' (toiling is a kind of working).
'introduced by' is a charade indicator (letters next to each other).
'english' becomes 'E' (abbreviation).
'toil' in reverse letter order is 'liot'.
'liot' put after 'e' is 'ELIOT'.
(Other definitions for eliot that I've seen before include "Practical Cats author" , "T S . . . . ., great poet of 'The Waste Land'" , "T.S. --, poet" , "Author of Adam Bede, d.1880" , "T S . . . . . wrote ''The Waste Land''" .)