n. clostridia1. spindle-shaped bacterial cell esp. one swollen at the center by an endospore. Syn. -- clostridia. [ WordNet 1.5 ]
2. [ capitalized ] 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). [ PJC ]