an elder statesman
an ˌelder ˈstatesman
1 a person who has had an important job in government, business, etc. and who, though he/she may have retired (= stopped work), is still likely to be asked for his/her opinion and advice
2 any experienced and respected person whose advice or work is valued: He is regarded as TV’s elder statesman, having worked for the giant CBS network for nearly twenty years.
See also: elder