seismograph

[ sahyz-muh-graf, -grahf, sahys- ]

noun

1. any of various instruments for measuring and recording the vibrations of earthquakes.

seismograph

/ saɪzˈmɒɡrəfə; ˌsaɪzməˈɡræfɪk; -ˌɡræf; ˈsaɪzməˌɡrɑːf /

noun

1. an instrument that registers and records the features of earthquakes. A seismogram ( ˈsaɪzməˌɡræm ) is the record from such an instrument Also calledseismometer

seismograph

/ sīz′mə-grăf′ /

1. An instrument that detects and records vibrations and movements in the Earth, especially during an earthquake. Most seismographs employ a pendulum mounted within a rigid framework and connected to a mechanical, optical, or electromagnetic recording device. When the Earth vibrates or shakes, inertia keeps the pendulum steady with respect to the movements of the frame, producing a graphic record of the duration and intensity of the Earth's movements. Separate instruments are needed to record the north-south horizontal, east-west horizontal, and vertical components of a tremor. By comparing the records produced by seismographs located in three or more locations across the Earth, the location and strength of an earthquake can be determined.

Derived Forms

• seisˈmography, noun
• seismographer, noun
• seismographic, adjective

Other Words From

• seis·mo·graph·ic [sahyz-m, uh, -, graf, -ik, sahys-], seismo·graphi·cal adjective

Word History and Origins

Origin of seismograph¹

First recorded in 1855–60; seismo- + -graph

Example Sentences

There are no seismographs anywhere near this volcano, or in Tonga, which is a real problem.

From Science News

Berger’s invention detected changes in spikes of voltage produced by our neurons—converting those signals into the seismograph-like squiggles popularized as “brain waves.”

From MIT Technology Review

Like a seismograph, the rings pick up the gravity disturbances, and the ring particles start to wiggle around.

From Popular-Science

The laser generates a line on a graph back at the lab, much like an earthquake-measuring seismograph, and if the ground shifts, that line wiggles a little bit.

From Voice of San Diego

He was curious to see the result as recorded on the seismograph, and to know at what hour it registered in Japan.

From Project Gutenberg

The following brief account of his seismograph will, therefore, form a not unsuitable complement to his Memoir.

From Project Gutenberg

When this is done, however, I trust that due notice will be given, so that the seismograph stations may have fair warning.

From Project Gutenberg

But even at noon the disturbance had not subsided, as slight shocks are recorded at frequent intervals on the seismograph.

From Project Gutenberg

The seismograph of to-day, however, has reached a stage of perfection where close approximations are obtained in the records made.

From Project Gutenberg