confrontation vs showdown

confrontation and showdown both are nouns.

Word	Noun	Adjective	Verb	Adverb
confrontation	Yes	No	No	No
showdown	Yes	No	No	No

As nouns, confrontation and showdown are synonyms defined as:

Other synonyms of confrontation include encounter, face-off.

confrontation (noun)	showdown (noun)
the act of hostile groups opposing each other	a hostile disagreement face-to-face
a focussed comparison; bringing together for a careful comparison
a hostile disagreement face-to-face
a bold challenge
discord resulting from a clash of ideas or opinions