Arguably highbrow point in unnoted opening talk (6,4)
I believe the answer is:
widows peak
'arguably highbrow point' is the definition.
'widow's peak' can be an answer for 'point' (widow's peak is a kind of point). I'm not sure about the 'arguably highbrow' bit.
'unnoted opening talk' is the wordplay.
'unnoted opening' becomes 'widow' (I can't explain this - if you can you should believe this answer much more).
'talk' becomes 'speak' (synonyms).
'widow'+'speak'='WIDOWS PEAK'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for widows peak that I've seen before include "V-shaped hairline" , "Barnet v remaining" .)