Non-professional friend inside gold ring's first (7)
I believe the answer is:
amateur
'non-professional' is the definition.
(I've seen this before)
'friend inside gold ring's first' is the wordplay.
'friend' becomes 'mate' (mate is a kind of friend**).
'inside' indicates putting letters inside.
'gold' becomes 'au' (Au is the chemical symbol for gold).
'first' says to take the initial letters.
The first letter of 'rings' is 'r'.
'mate' put inside 'au' is 'amateu'.
'amateu'+'r'='AMATEUR'
(Other definitions for amateur that I've seen before include "One is not professional" , "Non professional, eight across" , "inept player" , "he won't get paid" , "Dabbler" .)