Current unrest erupts, involving four becoming pushy (9)
I believe the answer is:
intrusive
'pushy' is the definition.
(I've seen this before)
'current unrest erupts involving four' is the wordplay.
'current' becomes 'i' (symbol for electric current).
'erupts' indicates anagramming the letters.
'involving' is an insertion indicator.
'four' becomes 'IV' (Roman numerals for four).
'unrest' is an anagram of 'ntruse'.
'ntruse' enclosing 'iv' is 'ntrusive'.
'i'+'ntrusive'='INTRUSIVE'
'becoming' is the link.
(Other definitions for intrusive that I've seen before include "disturbing" , "Presumptuous" , "Tending to enter uninvited" , "Pushy" , "Coming in uninvited" .)