Caviare free? That's materialism! (7)
I believe the answer is:
avarice
'materialism' is the definition.
Although both the answer and definition are singular nouns, I can't understand how one could define the other.
'caviare free?' is the wordplay.
'free?' is an anagram indicator (I've seen 'freed' mean this).
'caviare' anagrammed gives 'AVARICE'.
'that's' is the link.
Can you help me to learn more?
(Other definitions for avarice that I've seen before include "Insatiable desire for wealth" , "Insatiable lust" , "A deadly sin" , "One of seven deadly sins" , "Eager desire" .)