clostridium
clostridium , noun
1.
spindle-shaped bacterial cell esp. one swollen at the center by an endospore.
2.
a genus of anaerobic, spore-forming motile bacteria of the family Bacillaceae, including several pathogenic species, such as the causative agents of gas gangrene (Clostridium perfringens), botulism (Clostridium botulinum), and tetanus (Clostridium tetani). [capitalized]