Call for promotion of rank at centre (6)
I believe the answer is:
entail
'call for' is the definition.
(I've seen this before)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for entail that I've seen before include "Bring on an inevitable consequence" , "Late in (anag.)" , "settle estates for the long term" , "Involve (something) as an inevitable consequence" , "Involve or necessitate" .)