Denies running after a strong scent (7)
I believe the answer is:
aniseed
'strong scent' is the definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.
'denies running after a' is the wordplay.
'running' is an anagram indicator (the letters run around to different places).
'after' means one lot of letters go next to another.
'denies' anagrammed gives 'niseed'.
'niseed' after 'a' is 'ANISEED'.
Can you help me to learn more?
(Other definitions for aniseed that I've seen before include "Liquorice-flavoured seeds" , "Liquorice flavour" , "Aromatic flavouring" , "Eased in (anag)" , "Die sane (anag)" .)