/ Dictionary / Index S spirochete: Meaning and Definition of Find definitions for: spi•ro•chete Pronunciation: (spī'ru-kēt"), [key] — n. any of various spiral-shaped motile bacteria of the family Spirochaetaceae, certain species, as Treponema, Leptospira, and Borrelia, being pathogenic to humans and other animals, and other species being free-living, saprophytic, or parasitic. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: spirochete (Thesaurus) spiro- spirochetosis Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language