Middleman's oddly abandoned notion (4)

I believe the answer is:

idea

'notion' is the definition.
(both can mean a thought)

'middleman's oddly abandoned' is the wordplay.
'oddly abandoned' means one should take alternating letters (letters in odd-numbered positions removed).
The alternate letters of 'middleman' are 'IDEA'.

(Other definitions for idea that I've seen before include "Content of cognition" , "Light bulb above head" , "Creative spark" , "Inkling" , "Intention" .)

I've seen this clue in The Guardian.

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