Absence of oxygen is called what?

• A. Anoxia
• B. Anemia
• C. Dyspnea
• D. Angina

Answer: (A)

Anoxia is the term for a complete lack of oxygen. The prefix an- means without, and -oxia relates to oxygen, so anoxia literally describes oxygen being absent. It’s important to distinguish this from hypoxia, which is low oxygen, and from anemia, which is about reduced oxygen delivery due to problems with red blood cells or hemoglobin. Dyspnea is the sensation of difficult or labored breathing, not the absence of oxygen, and angina is chest pain from inadequate oxygen to the heart muscle, not the absence of oxygen overall. So the word that names the absence of oxygen is anoxia.