Exceptionally clever in leading experiments for the hair (12)
I believe the answer is:
brilliantine
'the hair' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
'exceptionally clever in leading experiments' is the wordplay.
'exceptionally clever' becomes 'brilliant' (I've seen this before).
'leading' says to take the initial letters.
The initial letter of 'experiments' is 'e'.
'brilliant'+'in'+'e'='BRILLIANTINE'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for brilliantine that I've seen before include "Hairdresser" , "preparation?" , "oil put on hair" , "this smooths the waves!" , "Scented hair oil" .)