The quality or state of being prosy; tediousness.(noun)
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Use "prosiness" in a sentence
"She repeats the word “wallpaper” twice in two lines of a poem—an unheard-of prosiness."
"The prosiness of the originators detracted nothing from the bravery of the movement."
"In his walk he strutted; and, in this respect, he bore a faint resemblance to the pigeon, as well as in a certain prosiness of speech, which might, in its monotony, be likened to the cooing of that bird."