Device that replaces nutriments (10)
I believe the answer is:
instrument
'device' is the definition.
(instrument is a kind of device)
'replaces nutriments' is the wordplay.
'replaces' indicates anagramming the letters (I've seen 'replaced' mean this).
'nutriments' is an anagram of 'INSTRUMENT'.
'that' is the link.
(Other definitions for instrument that I've seen before include "What's needed for 1 [MUSICIAN]" , "legal document" , "Word puzzle" , "power" , "Joanna, perhaps" .)