Uncovered partition over unnamed wooden stool (7)

I believe the answer is:

creepie

I'm a little stuck... Click here to teach me more about this clue!

'wooden stool' is the definition.
The definition suggests a singular noun which matches the answer.

'uncovered partition over unnamed' is the wordplay.
'uncovered' means to look at the middle letters.
'partition' becomes 'screen' (screen is a kind of partition).
'over unnamed' becomes 'pie' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
The centre of 'screen' is 'cree'.
'cree'+'pie'='CREEPIE'

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I've seen this clue in The Guardian.

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