Minder put off being foolish (9)
I believe the answer is:
imprudent
'foolish' is the definition.
(associated in meaning)
'minder put off' is the wordplay.
'off' indicates anagramming the letters.
'minder'+'put'='minderput'
'minderput' is an anagram of 'IMPRUDENT'.
'being' acts as a link.
(Other definitions for imprudent that I've seen before include "Without forethought" , "Reckless" , "Rash, lacking discretion" , "Lacking in good sense or caution" , "Unwise" .)