Even Johnson's initially working out notice for expulsion (8)
I believe the answer is:
ejection
'expulsion' is the definition.
(synonyms)
'even johnson's initially working out notice' is the wordplay.
'initially' suggests taking the first letters.
'working out' indicates anagramming the letters (an anagram must be worked out from the letters).
The initial letters of 'even johnson' is 'ej'.
'notice' with letters rearranged gives 'ection'.
'ej'+'ection'='EJECTION'
'for' is the link.
(Other definitions for ejection that I've seen before include "Discharge, expulsion" , "Throwing out - exile" , "Dismissal" , "Pilot's escape from plane" , "Forcible removal" .)