Sudden rush impressed English (8)
I believe the answer is:
stampede
'sudden rush' is the definition.
(I've seen this before)
'impressed english' is the wordplay.
'impressed' becomes 'stamped' (stamping is a kind of impressing).
'english' becomes 'e' (abbreviation).
'stamped'+'e'='STAMPEDE'
(Other definitions for stampede that I've seen before include "collective flight" , "Sudden rush of people" , "Panicky run" , "Sudden mass rush" , "Sudden mad rush" .)