Cut acerbic leader by journalist (4)
I believe the answer is:
axed
'cut' is the definition.
(I've seen this before)
'acerbic leader by journalist' is the wordplay.
'leader' suggests taking the first letters.
'by' becomes 'x' (2 by 4 is 2 x 4).
'journalist' becomes 'ed' (short for editor).
The initial letter of 'acerbic' is 'a'.
'a'+'x'+'ed'='AXED'
(Other definitions for axed that I've seen before include "Dismissed, given the chop" , "Sacked or terminated - with hatchet?" , "Chopped or terminated" , "removed" , "Felled" .)