foreshock [fawr-shok, fohr-] Word Origin noun Geology.
- a relatively small earthquake that precedes a greater one by a few days or weeks and originates at or near the focus of the larger earthquake.
Origin of foreshock First recorded in 1900–05;+ British Dictionary definitions for foreshock foreshock noun
- a relatively small earthquake heralding the arrival of a much larger one. Some large earthquakes are preceded by a series of foreshocksCompare