This African dictator bans special health supplement (7)
I believe the answer is:
thiamin
'health supplement' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
'this african dictator bans special' is the wordplay.
'african dictator' becomes 'amin' (Idi Amin, Ugandan dictator).
'bans' is a deletion indicator.
'special' becomes 'S' (common abbreviation as in Special Air Service).
'this'+'amin'='thisamin'
'thisamin' with 's' taken out is 'THIAMIN'.
Can you help me to learn more?
(Other definitions for thiamin that I've seen before include "food ingredient" , "vitamin required" , "Vitamin in cereals, beans, etc" , "Essential nutrition" , "Vitamin B 1" .)