ppmKK [ˋpiˋpiˋɛm] /ˈpiˈpiˈɛm/发音名词1百万分之一、百万分率缩写The water sample contained only two ppm of lead.这份水样中的铅含量只有百万分之二。2每分钟列印页数缩写,电脑This laser printer runs at about thirty ppm in black and white.这台雷射印表机的黑白列印速度约为每分钟三十页。用这个字练口说→