/ Dictionary / Index S seismo-: Meaning and Definition of Find definitions for: seismo- Pronunciation: [key] a combining form meaning “earthquake,” used in the formation of compound words: seismograph. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. seismism seismogram Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language