Parasitic or free-living bacteria

• Many pathogenic to humans and other animals

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Relapsing \Re*laps"ing\, a. Marked by a relapse; falling back; tending to return to a former worse state. Relapsing fever (Med.), an acute, epidemic, contagious fever, which prevails also endemically in Ireland, Russia, and some other regions. It is marked ...

Wiktionary Word definitions in Wiktionary
n. (alternative form of spirochaete English)

WordNet Word definitions in WordNet
n. parasitic or free-living bacteria; many pathogenic to humans and other animals [syn: spirochete ]

Wikipedia Word definitions in Wikipedia
Spirochaetes (also spelled spirochetes ) belong to a phylum of distinctive diderm (double-membrane) bacteria , most of which have long, helically coiled (corkscrew-shaped or spiraled, hence the name) cells . Spirochaetes are chemoheterotrophic in nature, ...