Fool with club that’s found in trunk (7)
I believe the answer is:
sapwood
'that's found in trunk' is the definition.
(a trunk might be made of sapwood)
'fool with club' is the wordplay.
'fool' becomes 'sap' (synonyms).
'with' says to put letters next to each other.
'club' becomes 'wood' (wood is a kind of club).
'sap'+'wood'='SAPWOOD'
(Another definition for sapwood that I've seen is " Rowan (among others) keeps this concealed".)
I've seen this clue in The Times.
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