"a shaking, a shock," from seio, "to move to and fro, to shake," chiefly with the idea of concussion (Eng., "seismic," "seismology," "seismometry"), is used (a) of a "tempest" in the sea, Matthew 8:24; (b) of "earthquakes," Matthew 24:7; 27:54; 28:2; Mark 13:8; Luke 21:11; Acts 16:26; Revelation 6:12; 8:5; 11:13 (twice) ,19; 16:18 (twice). See TEMPEST.