P波ぴーはピーはMeanings1nounP-wave; primary waveSeismological term for the compressional wave that arrives first during an earthquake.地じ震しんのとき、最さい初しょに感かんじる小ちいさな揺ゆれはP波はによるものです。During an earthquake, the small shaking you feel first is caused by P-waves.