Earthquake alarm

a bell signal constructed to operate on the theory that a few seconds before the occurrence of an earthquake the magnet temporarily loses its power.

See also: Earthquake

Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
Most buildings in the country, including the Batasang Pambansa Complex in Quezon City which is the headquarters of the House of Representatives, lack earthquake alarm systems and violate the National Building Code, 1-Pacman Rep.
"Right now that's the earthquake alarm going off, this is not a drill.
Radio and television stations will broadcast an earthquake alarm at 4pm, which will signal the start of the drill.
As a volunteer I had an earthquake alarm on my wall and a go-bag - luxuries many local people didn't have, but nevertheless the risk of an earthquake was always present.