Stalin’s colleague left to introduce uranium for energy, his final farewell? (6)
I believe the answer is:
burial
'energy his final farewell?' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'stalin's colleague left to introduce uranium' is the wordplay.
'stalin's colleague' becomes 'bria' (I can't justify this - if you can you should believe this answer much more).
'left' becomes 'l' (common abbreviation).
'to introduce' is an insertion indicator (to introduce to can mean to insert or include).
'uranium' becomes 'U' (U is the chemical symbol for uranium).
'bria'+'l'='brial'
'brial' enclosing 'u' is 'BURIAL'.
'for' is the link.
Can you help me to learn more?
(Other definitions for burial that I've seen before include "Concealing something under the ground" , "Getting put in the ground" , "ending" , "hiding" , "Interment or entombment" .)