Nametag changed by Bella (5)
I believe the answer is:
label
'nametag changed' is the definition.
I can't tell whether this definition defines the answer.
'bella' is the wordplay.
'bella' can be anagrammed to 'LABEL'.
But, I'm not clear how the anagram is indicated.
'by' is the link.
Can you help me to learn more?
(Other definitions for label that I've seen before include "Identity tag" , "Sticker" , "Tag; record company" , "attachment to the Christmas parcel" , "Put a name to" .)