Journalists want tip-off to break hot leading story (5)
I believe the answer is:
hacks
'journalists' is the definition.
(I've seen this before)
'want tip-off to break hot leading story' is the wordplay.
'want' becomes 'lack' (synonyms).
'tip-off' means to remove the first letter (one tip of the word is removed).
'to break' means one lot of letters goes inside another (inserted letters break the word apart).
'hot leading story' becomes 'hs' (I can't justify this - if you can you should give a lot more credence to this answer).
'lack' with its initial letter taken away is 'ack'.
'ack' inserted inside 'hs' is 'HACKS'.
Can you help me to learn more?
(Other definitions for hacks that I've seen before include "handles" , "Mediocre writers" , "Nags" , "Shack up with plain reporters" , "Reporters found in shack" .)