blindman's bluff vs blindman's buff

blindman's bluff and blindman's buff both are nouns.

Word	Noun	Adjective	Verb	Adverb
blindman's bluff	Yes	No	No	No
blindman's buff	Yes	No	No	No

As nouns, blindman's bluff and blindman's buff are synonyms defined as:

blindman's bluff and blindman's buff: a children's game in which a blindfolded player tries to catch and identify other players

blindman's bluff (noun)	blindman's buff (noun)
a children's game in which a blindfolded player tries to catch and identify other players	a children's game in which a blindfolded player tries to catch and identify other players