Meg returned valuable item (3)
I believe the answer is:
gem
'valuable item' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Perhaps there's a link between them I don't understand?
'meg returned' is the wordplay.
'returned' is a reversal indicator.
'meg' backwards is 'GEM'.
Can you help me to learn more?
(Other definitions for gem that I've seen before include "Treasured person" , "A precious stone like a diamond or emerald etc" , "A jewel or precious stone" , "36 Across or any other jewel" , "Pearl" .)