chronic fatigue syndrome

noun

: a disorder of unknown cause that is characterized by persistent profound fatigue usually accompanied by other symptoms (such as headache and tender lymph nodes) unrelated to any preexisting medical condition

—abbreviation CFS

Examples of chronic fatigue syndrome in a Sentence

Recent Examples on the Web

In rare cases, fatigue is caused by a condition called chronic fatigue syndrome. —Alexandria Nyembwe, Health, 7 Nov. 2025

Licorice Root Tea Licorice root tea reduces cortisol and mimics estrogen. Licorice root (Glycyrrhiza glabra) may lower cortisol (the stress hormone) and support adrenal health, which might help people with Addison’s disease or chronic fatigue syndrome. —Brandi Jones, Verywell Health, 18 Sep. 2025

But for those who do have issues with inflammation or allergies — like those with ulcerative colitis, rheumatoid arthritis, long COVID and chronic fatigue syndrome — Riggs believes the recipes she’s developed for the book would work well. —Caron Golden, San Diego Union-Tribune, 17 Sep. 2025

Technically known as myalgic encephalomyelitis and chronic fatigue syndrome (ME/CFS), the condition is marked by debilitating fatigue that doesn't go away with rest; cognitive impairment such as brain fog and difficulty focusing; sleep disturbances; and pain. —New Atlas, 25 July 2025

Word History

First Known Use

1947, in the meaning defined above

Rhymes for chronic fatigue syndrome

• acrosome
• aerodrome
• catacomb
• centrosome
• chromosome
• cytochrome
• hippodrome
• honeycomb
• liposome
• meerschaum
• metronome
• microtome

Medical Definition

chronic fatigue syndrome

noun

: a disorder of uncertain cause that is characterized by persistent profound fatigue usually accompanied by impairment in short-term memory or concentration, sore throat, tender lymph nodes, muscle or joint pain, and headache unrelated to any preexisting medical condition and that typically has an onset at about 30 years of age

—abbreviation CFS

called also myalgic encephalomyelitis