What operator of cannon will do as a lively person (8)
I believe the answer is:
fireball
'what operator of cannon will do as a lively person' is the definition.
The definition suggests a singular noun which matches the answer.
'will do as a lively person' is the wordplay.
I cannot really understand how this works, but
'will' could be 'll' (contracted form, as in 'he'll' - 'he will') and 'll' is present in the answer.
'a' is present in the answer.
'person' could be 'reb' (Reb is an example) and 'reb' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for fireball that I've seen before include "Large bright meteor" , "Bolide is its name in astronomy" , "Sphere of flame" , "Energetic type" , "Core of atomic explosion" .)