Daze, looking up at acorns, for example (4)

I believe the answer is:

nuts

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'acorns for example' is the definition.
I can't judge whether this defines the answer.

'daze looking up' is the wordplay.
'daze' becomes 'stun' (synonyms).
'looking up' is a reversal indicator (in a down clue, letters go up).
'stun' reversed gives 'NUTS'.

'at' acts as a link.

Can you help me to learn more?

(Other definitions for nuts that I've seen before include "Crazy (from Brazil?)" , "Stun (anag.)" , "Got a screw loose" , "Stun with hard fruits" , "Unbalanced" .)

I've seen this clue in The Daily Express.

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