Seismic/ˈsaɪzmɪk/ Definition 1 of 2Pro Tip 1/3Natural Disasters Use 'seismic' in discussions about earthquakes and the Earth's structure. Seismic activity was monitored after the volcano erupted. Pro Tip 2/3Scientific Terms Often appears in scientific or technical contexts involving Earth sciences. Researchers analyzed the seismic recordings from the ocean floor. Pro Tip 3/3Geographical Studies Common in geography studies, especially in plate tectonics and continental drift topics. The seismic map showed fault lines across the continent.