Late 16th century; earliest use found in Abraham Fleming (c1552–1607), author, literary editor, and Church of England clergyman. From potentate: see -acy.
Definition of potentacy in US English:
potentacy
nounˈpəʊtntəsi
rare
The state or rule of a potentate; supreme power.
Origin
Late 16th century; earliest use found in Abraham Fleming (c1552–1607), author, literary editor, and Church of England clergyman. From potentate: see -acy.