Setter flips about changed clue for atomic base (7)
I believe the answer is:
nucleus
'atomic base' is the definition.
The answer and definition can be both natural objects as well as being singular nouns.
Perhaps you can see an association between them that I can't see?
'setter flips about changed clue' is the wordplay.
'setter' becomes 'sun' (I've seen this in other clues).
'flips' says the letters should be written in reverse.
'about' means one lot of letters goes inside another.
'changed' indicates an anagram.
'sun' backwards is 'nus'.
'clue' anagrammed gives 'cleu'.
'nus' placed around 'cleu' is 'NUCLEUS'.
'for' is the link.
Can you help me to learn more?
(Other definitions for nucleus that I've seen before include "central component" , "Tiny central part of an atom" , "Core, centre" , "centrepiece?" , "Central mass of a cell" .)