Ornament from Norway acquired by purist (7)
I believe the answer is:
pendant
'ornament' is the definition.
(pendant is a kind of ornament)
'norway acquired by purist' is the wordplay.
'norway' becomes 'n'.
'acquired by' means one lot of letters goes inside another.
'purist' becomes 'pedant' (I've seen this before).
'n' put within 'pedant' is 'PENDANT'.
'from' acts as a link.
(Other definitions for pendant that I've seen before include "Panted after learned one" , "Ornament hanging from necklace" , "earring, say" , "item suspended" , "One hung by the neck" .)