Half of Europe welcome Oman returning charm (7)
I believe the answer is:
enamour
'charm' is the definition.
(I know that charm can be written as enamour)
'half of europe welcome oman returning' is the wordplay.
'half of' indicates taking half.
'welcome' is an insertion indicator (in sense of 'inviting in').
'returning' is a reversal indicator.
'oman' reversed gives 'namo'.
'europe' cut in half is 'eur'.
'eur' going around 'namo' is 'ENAMOUR'.
(Other definitions for enamour that I've seen before include "sweep one off one's feet" , "Our name (anag)" , "Charm, captivate" , "Enchant" , "Delight" .)