1. A genus of bacteria that causes a serious respiratory infection, typically transmitted through contaminated water systems.
Usage: Usually capitalized when referring to the genus; Medical/scientific term
2. The disease caused by infection with Legionella bacteria, characterized by pneumonia-like symptoms.
Usage: Often used in lowercase in general contexts; Also called Legionnaires' disease

Examples

• The outbreak was traced to Legionella contamination in the building's cooling system.
• Legionella bacteria thrive in warm water environments like air conditioning units.
• Public health officials tested the water supply for legionella after several cases were reported.
• Proper maintenance of water systems can prevent legionella growth.
• The patient was diagnosed with legionella pneumonia after exposure to contaminated water.
• Legionella outbreaks are rare but can be serious if left untreated.