Working hard in Bermondsey, engaged by sign painter (8)
I believe the answer is:
leonardo
'painter' is the definition.
(Leonardo is an example)
'working hard in bermondsey engaged by sign' is the wordplay.
I cannot quite see how this works, but
'working' could be 'on' (on can mean working or activated) and 'on' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for leonardo that I've seen before include "and 12 Across: Renaissance genius" , "Italian boy" , "Da Vinci and DiCaprio" , "Great Italian artist ........ da Vinci" , "Great painter of the Mona Lisa, . . . . . . . . da Vinci" .)