Communist leader, one with brightly coloured hair (7)
I believe the answer is:
redhead
'one with brightly coloured hair' is the definition.
(someone with red hair)
'communist leader' is the wordplay.
'communist' becomes 'red' (red can informally mean communist).
'leader' becomes 'head' (head is a kind of leader).
'red'+'head'='REDHEAD'
(Other definitions for redhead that I've seen before include "Auburn type" , "One with rufous hair" , "Fergie perhaps" , "member of ginger group?" , "Person with carroty hair" .)