Doc could be a bit of a comedian! (6)
I believe the answer is:
medico
'doc' is the definition.
(synonyms)
'a bit of a comedian' is the wordplay.
I cannot really understand how this works, but
'bit' could be 'o' (resembles 0, a binary digit or bit) and 'o' is found within the answer.
The remaining letters 'medic' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'could be' acts as a link.
Can you help me to learn more?
(Other definitions for medico that I've seen before include "quack" , "Health practitioner" , "Doctor" .)