Charm in part of capital is manifest (8)
I believe the answer is:
talisman
'charm' is the definition.
(I know that talisman is a type of charm)
'part of capital is manifest' is the wordplay.
'part of' indicates a hidden word.
'TALISMAN' is hidden in the letters of 'capital is manifest'.
'in' is the link.
(Other definitions for talisman that I've seen before include "Object with magical power" , "which is charming" , "Magically protective object" , "Stone thought to have magical powers" , "Liam, Stan has charm." .)