In turning up one idiot, finding another (6)
I believe the answer is:
nitwit
'finding another' is the definition.
I can't tell whether this definition defines the answer.
'in turning up one idiot' is the wordplay.
'turning up' shows that the letters should be reversed in order.
'one idiot' becomes 'twit' (both can mean a stupid person).
'in' reversed gives 'ni'.
'ni'+'twit'='NITWIT'
Can you help me to learn more?
(Other definitions for nitwit that I've seen before include "Informally a stupid person, like funny flea?" , "Blockhead" , "Fool, idiot" , "Simpleton" , "Silly person (colloq.)" .)