commander vs commandant

commander and commandant both are nouns.

Word	Noun	Adjective	Verb	Adverb
commander	Yes	No	No	No
commandant	Yes	No	No	No

As nouns, commander and commandant are synonyms defined as:

Other synonyms of commander include commanding officer.

commander (noun)	commandant (noun)
an officer in command of a military unit	an officer in command of a military unit
a commissioned naval officer who ranks above a lieutenant commander and below a captain
an officer in the airforce
someone in an official position of authority who can command or control others