Definition of "apropos of nothing" [apropos of nothing]
Without reference to anything.(phrase)
Without any apparent reason or purpose.(phrase)
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Use "apropos of nothing" in a sentence
"And again, later, apropos of nothing but what one guessed from the dreamer's expressive face, he said: "I had remembered it as so much larger" -- indicating the square -- "until I saw it again when we came down with the army.""