Kind of ring, jewellery worn by soldier (8)
I believe the answer is:
obliging
'kind' is the definition.
(thesaurus)
'ring jewellery worn by soldier' is the wordplay.
'ring' becomes 'O' (letter resembling a ring).
'jewellery' becomes 'bling' (informal term for jewellery).
'worn by' means one lot of letters goes inside another (outside letters are worn by those on the inside).
'soldier' becomes 'GI' (term for US soldier).
'bling' enclosing 'gi' is 'bliging'.
'o'+'bliging'='OBLIGING'
'of' acts as a link.
(Other definitions for obliging that I've seen before include "Agreeable" , "Courteous and helpful, willing to do a favour" , "Compelling" , "Cheerfully willing to do favours" , "pleasant" .)