seism

1 of 2

noun

ˈsīzəm
plural -s
: earthquake sense 1

seism

2 of 2

noun combining form

ˌsīzəm
plural -s
: seismic movement
tachyseism

Word History

Etymology

Noun

Greek seismos

Noun combining form

Greek seismos earthquake

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Browse Nearby Words

seisin
seism
seismal
See all Nearby Words

Cite this Entry

“Seism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/seism. Accessed 1 Sep. 2026.

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Kids Definition

seism-

combining form
variants or seismo-
: earthquake : vibration
seismograph
Etymology

Combining form

Greek seismos "earthquake," from seiein "to shake"

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