First lady amid nouveaux riches primarily? Certainly not! (5)
I believe the answer is:
never
'not' is the definition.
(thesaurus)
'first lady amid nouveaux riches primarily?' is the wordplay.
'first lady' becomes 'eve' (first woman in the Bible).
'amid' indicates putting letters inside.
'primarily?' says to take the initial letters (I've seen 'primarily' mean this).
The initial letters of 'nouveaux riches' is 'nr'.
'eve' going within 'nr' is 'NEVER'.
'certainly' is the link.
This may not be right. It may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for never that I've seen before include "' - - Say - - Again': Bond film" , "Not in a million years!" , "Emphatic negative" , "Certainly not!" , "On no occasion" .)