What does pneumonia mean?
Pneumonia is a disease of the lungs in which the tiny air sacs, called alveoli, become inflamed and may fill with fluid, pus, or other material. The result can be a persistent cough, fever, chest pain, shortness of breath, and low oxygen levels. Although people often use the word to mean a bacterial chest infection, pneumonia may also result from viruses, fungi, or chemical exposure. In medicine, the term can refer more broadly to lung inflammation, not only infection. Doctors diagnose pneumonia using a combination of symptoms, examination, blood tests, and often chest imaging. Treatment depends on the cause and severity: antibiotics may be appropriate for bacterial pneumonia, while viral cases require supportive care such as fluids, oxygen, and rest. Pneumonia can be especially serious for infants, older adults, and people with weakened immune systems or chronic heart or lung disease. Prompt medical attention is important when breathing becomes difficult or symptoms worsen.
nounPneumonia is an infection of the lungs that causes the air sacs to become inflamed and may fill with fluid or pus, making breathing difficult. It can be caused by bacteria, viruses, fungi, or the inhalation of harmful substances such as food or vomit.
- An infectious or inflammatory disease of the lungs in which the air sacs become filled with fluid or other material, causing coughing, fever, breathing difficulty, and reduced oxygen levels.
"Her doctor diagnosed pneumonia after the persistent cough and fever worsened."
"The elderly patient was hospitalized with severe pneumonia."
"Vaccination can reduce the risk of serious illness from influenza and pneumonia."
The standard plural is “pneumonias,” though the word is usually used in the singular when referring to the disease in general.
"The complications included several cases of pneumonias after surgery."
Pneumonia takes its name from the Greek word for lung, a fitting origin for a disease that can make every breath difficult.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does pneumonia come from?
Pneumonia comes from Greek pneumōn, meaning “lung,” combined with the suffix -ia, used in the formation of names of diseases and medical conditions. The word entered English through Latin and refers to inflammation of the lungs. Its relatives include pulmonary, pneumonic, pneumatic, and pneumatics, all of which ultimately derive from Greek roots associated with air, breathing, or the lungs.
Related word forms
How pneumonia is actually used
In general use, pneumonia usually refers to an infection of the lungs. Medical literature also uses the term more broadly for inflammation of lung tissue, including noninfectious causes such as aspiration or certain autoimmune diseases. The word is normally used in general and clinical contexts.
Easily confused with pneumonia
Bronchitis is inflammation of the bronchial tubes that carry air to and from the lungs, whereas pneumonia is an infection of the lung tissue itself.
A pulmonary embolism is a blockage of an artery in the lung, usually caused by a blood clot, rather than an infection of the lungs.