n. [ Micro- + Gr. &unr_; an earthquake, fr. &unr_; to shake. ] A feeble earth tremor not directly perceptible, but detected only by means of specially constructed apparatus. -- Mi`cro*seis"mic Mi`cro*seis"mic*al a. [ Webster 1913 Suppl. ]

n. [ Microseiem + -graph. ] A microseismometer; specif., a microseismometer producing a graphic record. [ Webster 1913 Suppl. ]

n. [ Microseiem + -logy. ] Science or study of microseisms. [ Webster 1913 Suppl. ]

n. [ Microseism + -meter. ] A seismometer for measuring amplitudes or periods, or both, of microseisms. -- Mi`cro*seis*mom"e*try n. [Webster 1913 Suppl.]