Wind-up merchants in playground serve nuts around one (9)
I believe the answer is:
receivers
'wind-up merchants' is the definition.
I can't tell whether this definition defines the answer.
'playground serve nuts around one' is the wordplay.
'playground' becomes 'rec' (short for recreation ground).
'nuts' is an anagram indicator (nuts can mean crazy).
'around' indicates putting letters inside.
'one' becomes 'i' (Roman numeral).
'serve' with letters rearranged gives 'evers'.
'evers' enclosing 'i' is 'eivers'.
'rec'+'eivers'='RECEIVERS'
'in' is the link.
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