South African dead, leader gone, howl in grief (7)
I believe the answer is:
ululate
'howl in grief' is the definition.
(I've seen this in another clue)
'south african dead leader gone' is the wordplay.
'south african' becomes 'zulu' (I've seen this before).
'dead' becomes 'late' (similar in meaning).
'leader gone' means to remove the first letter.
'zulu'+'late'='zululate'
'zululate' with its first letter removed is 'ULULATE'.
(Other definitions for ululate that I've seen before include "Give a hoot" , "Express grief" , "Howl with grief" , "Emit long, loud wails" , "Howl, wail, screech" .)