Glossary of COPD Terms

Last updated: August 2023


Alpha-1 antitrypsin deficiency (alpha-1)

A genetic disorder passed down in families. Having this deficiency can put people at a higher risk for COPD.1,2


Millions of tiny sacs located in the lungs. In the alveoli, oxygen gets absorbed into the blood, and carbon dioxide is released.1


Medicine for bacteria infection.1


Drugs that relax muscles in the airways, which improves airflow. They are used as rescue relievers and controllers.1

Arterial blood gas

This is a blood test that looks at oxygen and carbon dioxide in the blood. In this test, a sample of blood is taken from an artery, often in your wrist or arm.1



Drugs that relax muscles in the airways to improve airflow. They are primarily used as a daily drug for breathing problems. They can also be taken as needed for quick relief.1

BiPAP (bilevel positive airway pressure)

A BiPAP machine makes breathing easier by sending pressurized air into your airways through a close-fitting mask. It is commonly used in emergency departments or hospitals.1

Bronchial tubes

Larger airways located in the lungs.1


This refers to the smaller airways in the lungs that lead to the alveoli.1


Drugs that relax the muscles in the airways. They are often used as rescue relievers and controllers.1,2



Plastic tubing that provides oxygen through the nose.1

Chest physiotherapy

This is a treatment performed by respiratory therapists to reduce mucus buildup.1

Chronic bronchitis

An ongoing (chronic) condition where the airways of the lungs produce extra mucus. The airways can become damaged, making it harder to breathe. Chronic bronchitis and emphysema are the most common types of COPD.1-3


Small, hair-like fibers that line the bronchial tubes in the lungs. These fibers help move mucus up through the tubes so it can be coughed out.1

COPD (chronic obstructive pulmonary disease)

A chronic lung disease where ongoing airflow limitation makes it difficult to breathe. It can include conditions such as chronic bronchitis and emphysema.2,3


Medicines that reduce inflammation in your lungs. Corticosteroids can be inhaled or taken by mouth (orally). These drugs reduce inflammation by imitating hormones produced by the adrenal glands.1

CPAP (continuous positive airway pressure)

The delivery of pressure and airflow to your lungs. This can assist with keeping your airways open. CPAP can be delivered with a ventilator or through a smaller bedside machine.1



The diaphragm is the primary muscle used for breathing. It separates the chest cavity from the stomach.1


A condition when you feel shortness of breath or difficulty breathing.1



A condition where the lungs are affected, causing damage to the alveoli. This results in difficulty breathing.1-3


Exacerbations are when COPD symptoms worsen. You may need changes in medical treatment if you have exacerbations.1



This is when you begin to breathe rapidly due to lung damage. It can also be a result of feeling nervous or upset.1


When there is a lack of oxygen in the body.1



A handheld portable device that delivers medicine to your lungs and assists breathing. It can contain steroids as well to prevent inflammation.1,2


A procedure where a tube is inserted through the nose or mouth and into the lungs to provide breathing assistance.1



A device that supplies liquid medicines through a spray or mist. It allows you to take drugs directly into the lungs.1

Noninvasive ventilation (NIV)

This refers to a mask that provides breathing support. An example of this would be a BiPAP machine.1


Oxygen concentrator

A medical device that takes oxygen from the air and sends it through a long narrow tube into the nose. Oxygen concentrators are used for oxygen therapy.1

Oxygen therapy

A medically prescribed system of providing additional oxygen to the body. It is used when diseased lungs cannot meet the oxygen needs of the body.1,2


Phosphodiesterase-4 inhibitor (PDE-4 inhibitor)

A drug that helps lower airway inflammation. It can also limit COPD exacerbations.1


An infection of one or both lungs that can be caused by bacteria, fungi, or viruses.1,2

Pulmonary rehabilitation

A medical program for people living with lung diseases. A pulmonary rehab program may include:1,2

  • Exercise training
  • Health education
  • Emotional support
  • Breathing techniques

Pulse oximetry

A test that examines the amount of oxygen in your blood and will reveal if oxygen therapy is necessary. In this test, a sensor with a light is placed on your finger or ear.1


Respiratory therapist

A healthcare professional specialized in providing respiratory care to people with lung diseases, including COPD.1,3


Sleep apnea

A sleep condition where you can stop breathing while sleeping. Your breathing can also be too shallow during sleep.1


A type of lung function breathing test that measures the amount of air you can take into your lungs. It can assess how quickly you can exhale and help diagnose lung diseases.1,3


Sputum, also called phlegm, is airway mucus and some saliva that are coughed up when clearing the airways.1,3



This is a medicine that assists breathing by helping open up the airways.1


The trachea, also called the windpipe, is the largest airway in the respiratory system.1


A breathing tube that is placed in the neck and can be used for longer-term ventilation.1