diplomate

[dip-luh-meyt] /ˈdɪp ləˌmeɪt/
noun
1.
a person who has received a diploma, especially a doctor, engineer, etc., who has been certified as a specialist by a board within the appropriate profession.
Origin
1875-80; diplom(a) + -ate1
Can be confused
diplomat, diplomate.
British Dictionary definitions for diplomate

diplomate

/ˈdɪpləˌmeɪt/
noun
1.
any person who has been granted a diploma, esp a physician certified as a specialist
diplomate in Medicine

diplomate dip·lo·mate (dĭp'lə-māt')
n.
One who has received a diploma, especially a physician certified as a specialist by a board of examiners.