downfall vs anticlimax

downfall and anticlimax both are nouns.

Word	Noun	Adjective	Verb	Adverb
downfall	Yes	No	No	No
anticlimax	Yes	No	No	No

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

downfall (noun)	anticlimax (noun)
a sudden decline in strength or number or importance	a change from a serious subject to a disappointing one
failure that results in a loss of position or reputation	a disappointing decline after a previous rise
the falling to earth of any form of water (rain or snow or hail or sleet or mist)