dictator vs autocrat

dictator and autocrat both are nouns.

Word	Noun	Adjective	Verb	Adverb
dictator	Yes	No	No	No
autocrat	Yes	No	No	No

As nouns, autocrat is a hyponym of dictator; that is, autocrat is a word with a more specific, narrower meaning than dictator:

Other hyponyms of dictator include shogun, strongman, despot, tyrant.

dictator (noun)	autocrat (noun)
a ruler who is unconstrained by law	a cruel and oppressive dictator
a person who behaves in a tyrannical manner
a speaker who dictates to a secretary or a recording machine