Captivate leader of orchestra in eastern part of Belgium (7)
I believe the answer is:
enamour
'captivate' is the definition.
(I know that captivate can be written as enamour)
'leader of orchestra in eastern part of belgium' is the wordplay.
'leader of' suggests taking the first letters.
'in' is an insertion indicator.
'eastern' becomes 'e'.
'part of belgium' becomes 'namur' (I can't explain this - if you can you should give a lot more credence to this answer).
The initial letter of 'orchestra' is 'o'.
'e'+'namur'='enamur'
'o' going within 'enamur' is 'ENAMOUR'.
Can you help me to learn more?
(Other definitions for enamour that I've seen before include "Enchant" , "entrance" , "Our name (anag)" , "Inspire with love; charm" , "Fill with love" .)