Journalist on island made small advances (6)
I believe the answer is:
inched
'made small advances' is the definition.
'journalist on island' is the wordplay.
'journalist' becomes 'ed' (short for editor).
'on' says to put letters next to each other.
'island' becomes 'inch' (I've seen this before).
'ed' put after 'inch' is 'INCHED'.
(Other definitions for inched that I've seen before include "Moved by slow degrees" , "Moved gradually" , "Moved in small increments" , "Moved along very slowly" .)