Confidence as ace runs round the bend? (9)
I believe the answer is:
assurance
'confidence' is the definition.
(synonyms)
'as ace runs round the bend?' is the wordplay.
'round the bend?' is an anagram indicator (I've seen 'round the bend' mean this).
'ace'+'runs'='aceruns'
'aceruns' with letters rearranged gives 'surance'.
'as'+'surance'='ASSURANCE'
(Other definitions for assurance that I've seen before include "Cure an ass of a feeling of certainty" , "(Life) cover" , "Guarantee - belief in oneself" , "Certainty; life insurance" , "what may follow life" .)