Greek character left nothing for Byzantine scientist (5)
I believe the answer is:
philo
'byzantine scientist' is the definition.
I don't know anything about this answer so I can't tell whether this works.
'greek character left nothing' is the wordplay.
'greek character' becomes 'phi' (letter from the Greek alphabet).
'left' becomes 'l' (common abbreviation).
'nothing' becomes 'O' (looks like zero - 0).
'phi'+'l'+'o'='PHILO'
'for' acts as a link.
Can you help me to learn more?
(Another definition for philo that I've seen is " On film, he kept Clyde".)