Medical Definition of Spirochaeta
: a genus (the type of the family spirochaetaceae) of spirochetes distinguished by a flexible undulating body with the protoplasm wound spirally around an elastic axis filament and comprising as now restricted various chiefly aquatic forms or formerly these together with important pathogens now placed in the genera Treponema, Borrelia, and Leptospira
Seen and Heard
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