US Medical Term · anatomy
Alveoli
Alvéolos
In 9 languages
| Language | Term |
|---|---|
| English | Alveoli |
| Spanish (Español) | Alvéolos |
| Chinese (中文) | 肺泡 |
| Korean (한국어) | 폐포 |
| Vietnamese (Tiếng Việt) | Phế nang |
| Filipino (Tagalog) | Albeolo |
| Portuguese (Português) | Alvéolos |
| Thai (ภาษาไทย) | ถุงลมปอด |
| Japanese (日本語) | 肺胞 |
What it means
Alveoli are the tiny, balloon-shaped air sacs at the very end of the airways inside your lungs. There are about 300 million of them in each lung, and together they provide a huge surface area — roughly the size of a tennis court — where oxygen from the air you breathe passes into your bloodstream, and carbon dioxide, a waste gas, passes out so you can exhale it. The walls of the alveoli are extremely thin, just one cell thick, to allow this gas exchange to happen quickly. Conditions like pneumonia, COVID-19, and emphysema can damage or fill the alveoli with fluid, making it hard to breathe and reducing the oxygen level in your blood.
How to say it
Sentences a patient might use with a doctor, nurse, pharmacist, or insurer:
My doctor said the pneumonia filled some of my alveoli with fluid and that is why my oxygen was low.
Mi médico dijo que la neumonía llenó algunos alvéolos de líquido y por eso mi oxígeno estaba bajo.
I have emphysema — can the damaged alveoli in my lungs repair themselves?
Tengo enfisema. ¿Pueden repararse los alvéolos dañados en mis pulmones?
The nurse explained that the oxygen mask helps push air into my alveoli so my blood gets enough oxygen.
La enfermera explicó que la mascarilla de oxígeno ayuda a empujar aire hacia mis alvéolos para que mi sangre reciba suficiente oxígeno.
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Sources
Last reviewed: September 2026