chronic fatigue syndrome

American  

noun

1. a viral disease of the immune system, usually characterized by debilitating fatigue and flu-like symptoms.

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chronic fatigue syndrome British  

noun

1.  CFS.  another name for myalgic encephalopathy

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chronic fatigue syndrome Scientific  

1. A syndrome characterized by debilitating fatigue and a combination of flulike symptoms such as sore throat, swollen lymph glands, low-grade fever, headache, and muscle pain or weakness. The cause is unknown.

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chronic fatigue syndrome Cultural  

1. A condition characterized by fatigue over an extended period, sometimes accompanied by neurologic abnormalities. The cause of this syndrome is unknown.

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Etymology

Origin of chronic fatigue syndrome

First recorded in 1988

Example Sentences

Healthy individuals had more of these bacteria than people with conditions such as inflammatory bowel disease, obesity, and chronic fatigue syndrome.

From Science Daily • Feb. 14, 2026

Among the most common co-occurring illnesses were chronic fatigue syndrome and mast cell activation syndrome, or MCAS, a condition where patients experience intense episodes of diarrhea, hives, vomiting, and, in many cases, life-threatening anaphylaxis attacks.

From Slate • Sep. 15, 2025

Ms Beck, 63, who suffers from myalgic encephalomyelitis, which is also known as chronic fatigue syndrome, said she had planned to visit the area soon.

From BBC • Apr. 12, 2025

Shannon Doulis' life changed after she contracted Covid-19 four years ago, later developing chronic fatigue syndrome and fibromyalgia as a result of long Covid.

From BBC • Mar. 31, 2025

By giving the condition a name like "lymphoma" or "melanoma", "chronic fatigue syndrome" "Epstein-Barr syndrome" or "AIDS," "systemic yeast infection", "hepatitis" or what have, people think the doctor then understands their disease.

From How and When to Be Your Own Doctor by Solomon, Steve