despotic vs authoritarian

despotic is not a noun while authoritarian is a noun.

Word	Noun	Adjective	Verb	Adverb
despotic	No	Yes	No	No
authoritarian	Yes	Yes	No	No

As adjectives, despotic and authoritarian are synonyms defined as:

despotic and authoritarian: characteristic of an absolute ruler or absolute rule; having absolute sovereignty

Other synonyms of despotic include autocratic, dictatorial, tyrannic, tyrannical.

despotic (noun)	authoritarian (noun)
	a person who behaves in a tyrannical manner

despotic (adjective)	authoritarian (adjective)
belonging to or having the characteristics of a despot	expecting unquestioning obedience
characteristic of an absolute ruler or absolute rule; having absolute sovereignty	characteristic of an absolute ruler or absolute rule; having absolute sovereignty
ruled by or characteristic of a despot