To gain access, use a jemmy, showing boldness (10)
I believe the answer is:
enterprise
'boldness' is the definition.
(thesaurus)
'to gain access use a jemmy' is the wordplay.
I cannot really see how this works, but
'jemmy' could be 'prise' (both can mean to force something open) and 'prise' is found within the answer.
'gain access' could be 'enter' (I've seen this in another clue) and 'enter' is present in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
'showing' is the link.
Can you help me to learn more?
(Other definitions for enterprise that I've seen before include "business concern" , "Company" , "audacity" , "Bold resourcefulness" , "Get-up-and-go - venture" .)