Simple past tense and past participle of snowball. (verb)
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Use "snowballed" in a sentence
"Being snowballed is part of being out doors during snowy weather."
"But this thing kind of snowballed much larger than I ever imagined when we started with one person."
"" It just kind of snowballed as the weeks went by and suddenly the film was front page news, a ' phenomenon of society, ' " says Etienne Comar, who produced and co-scripted " Of Gods and Men " with Mr. Beauvois."