snowball
n mass of snow pressed into a hard ball for throwing in play 雪球
children throwing snowballs at each other 打雪仗的儿童. v [I]
1 throw snowballs 掷雪球; 打雪仗
children snowballing in the park 在公园打雪仗的儿童.
2 (fig 比喻) grow quickly in size, importance, etc （体积、 重要性等）（像滚雪球般）迅速增大
Opposition to the war snowballed. 反战情绪急速增长.