Look to oust broadcaster's central position in syndicate (4)
I believe the answer is:
bloc
'position in syndicate' is the definition.
'bloc' can be an answer for 'syndicate' (thesaurus). I am not certain of the 'position in' bit.
'look to oust broadcaster's central' is the wordplay.
'look' becomes 'lo' ('lo' is an archaic exclamation meaning 'look!').
'to' says to put letters next to each other (I've seen this in other clues).
'oust broadcaster' becomes 'b' (I am not sure about this - if you are sure you should believe this answer much more).
'central' becomes 'c' (common abbreviation in various government acronyms).
'lo' after 'b' is 'blo'.
'blo'+'c'='BLOC'
Can you help me to learn more?
(Other definitions for bloc that I've seen before include "A number of countries" , "Group with a common policy" , "Alliance - coalition" , "multinational group" , "Political coalition" .)