Magic is in spell on peak in Africa (8)
I believe the answer is:
charisma
'magic' is the definition.
(thesaurus)
'is in spell on peak in africa' is the wordplay.
'in' is an insertion indicator.
'spell' becomes 'charm' (a charm is a magic spell).
'on' is a charade indicator (letters next to each other).
'peak in' says to take the initial letters (in a down clue, the letter at the top of the word).
The initial letter of 'africa' is 'a'.
'is' going within 'charm' is 'charism'.
'charism'+'a'='CHARISMA'
(Other definitions for charisma that I've seen before include "it inspires loyalty" , "Capacity to inspire enthusiasm" , "Personal magnetism, great charm" , "Personal magnetism -- archaism (anag)" , "Personal attractiveness" .)