Throw out measure restricting European power (6)
I believe the answer is:
depose
'throw out' is the definition.
(deposing is a kind of throwing out)
'measure restricting european power' is the wordplay.
'measure' becomes 'dose' (dose is a kind of measure**).
'restricting' means one lot of letters goes inside another.
'european' becomes 'e' (abbreviation e.g. EU).
'power' becomes 'p'.
'e'+'p'='ep'
'dose' going around 'ep' is 'DEPOSE'.
(Other definitions for depose that I've seen before include "Remove from office or position" , "Remove from office; testify" , "Oust from throne" , "Forcibly oust from office" , "Remove from top position" .)