Caper with terrible actor outside Venice opening (6)
I believe the answer is:
cavort
'caper' is the definition.
(thesaurus)
'terrible actor outside venice opening' is the wordplay.
'terrible' indicates an anagram.
'outside' is an insertion indicator.
'opening' suggests taking the first letters.
The first letter of 'venice' is 'v'.
'actor' with letters rearranged gives 'caort'.
'caort' placed around 'v' is 'CAVORT'.
'with' acts as a link.
(Other definitions for cavort that I've seen before include "Caper about excitedly" , "Prance around" , "Frolic joyfully" , "Lark about, frolic" , "Dance around excitedly" .)