Making clear to one, with a hint (8)
I believe the answer is:
overtone
'hint' is the definition.
(overtone can mean an implication or hint)
'making clear to one with a' is the wordplay.
'making clear' becomes 'overt' (I can't explain this - if you can you should give a lot more credence to this answer).
'to one with' means one lot of letters go next to another.
'a' becomes 'one'.
'overt'+'one'='OVERTONE'
Can you help me to learn more?
(Other definitions for overtone that I've seen before include "Subtle extra meaning" , "Subtle quality" , "Hint" , "part of harmonic series" , "Innuendo perhaps" .)