The flagpole stood as straight as a broomstick in the center of the square.

broomstick 是由 broom（扫帚）和 stick（棍子）组成的复合名词，字面意思是"扫帚的棍状部分"，即"扫帚柄"。在比喻中常用来形容笔直坚硬的物体。