argue vs expostulate

argue and expostulate both are verbs.

Word	Noun	Adjective	Verb	Adverb
argue	No	No	Yes	No
expostulate	No	No	Yes	No

As verbs, expostulate is a hyponym of argue; that is, expostulate is a word with a more specific, narrower meaning than argue:

Other hyponyms of argue include re-argue, defend, fend for, support.

argue (verb)	expostulate (verb)
have an argument about something	reason with (somebody) for the purpose of dissuasion
give evidence of
present reasons and arguments