Nick lived in backwardness (5)
I believe the answer is:
devil
'backwardness' is the definition.
Although both the answer and definition are singular nouns, I don't see how one could define the other.
'nick lived' is the wordplay.
'lived' can be anagrammed to 'DEVIL'.
Though, I'm unsure how the anagram is indicated.
'in' acts as a link.
Can you help me to learn more?
(Other definitions for devil that I've seen before include "Powerful evil spirit" , "Unsurpassed" , "Coat spicily; do hackwork" , "Imp" , "Lived with Satan" .)