Mature fellow given a fresh start (6)
I believe the answer is:
mellow
'mature' is the definition.
(I've seen this before)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for mellow that I've seen before include "Ripe, soft" , "Of wines, well matured and smooth" , "Aged to full flavour" , "Softened by maturity" , "Laid-back or pleasantly smooth" .)