duologue vs dialog

duologue and dialog both are nouns.

Word	Noun	Adjective	Verb	Adverb
duologue	Yes	No	No	No
dialog	Yes	No	No	No

As nouns, dialog is a hypernym of duologue; that is, dialog is a word with a broader meaning than duologue:

duologue: a part of the script in which the speaking roles are limited to two actors
dialog: the lines spoken by characters in drama or fiction

Other hypernyms of duologue include dialogue.

As nouns, duologue and dialog are synonyms defined as:

Other synonyms of duologue include dialogue.

duologue (noun)	dialog (noun)
a part of the script in which the speaking roles are limited to two actors	the lines spoken by characters in drama or fiction
a conversation between two persons	a conversation between two persons
	a literary composition in the form of a conversation between two people