board of directors vs directorate

board of directors and directorate both are nouns.

Word	Noun	Adjective	Verb	Adverb
board of directors	Yes	No	No	No
directorate	Yes	No	No	No

As nouns, board of directors and directorate are synonyms defined as:

board of directors and directorate: a group of persons chosen to govern the affairs of a corporation or other large institution

board of directors (noun)	directorate (noun)
a group of persons chosen to govern the affairs of a corporation or other large institution	a group of persons chosen to govern the affairs of a corporation or other large institution