: a potentially life-threatening, systemic response of the immune system that results from the spread of pathogenic agents (such as bacteria or viruses) and their toxins to the bloodstream from a localized infection (as of the lungs), that involves both inflammatory and immunosuppressive activity, that is marked especially by fever, chills, rapid heart rate and breathing, fatigue, confusion, increased blood coagulation, hypotension, impaired microcirculation, and organ dysfunction, and that may progress to septic shock

Note: The primary cause of sepsis is pneumonia with secondary causes commonly including infections of the abdominal cavity and urinary tract.

compare septicemia

Examples of sepsis in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The lactate signal is a performance indicator for athletes and a potential sign of sepsis or organ failure. Hanna Wickes, Charlotte Observer, 2 Sep. 2026 According to the Sepsis Alliance, depression is among the symptoms of post-sepsis syndrome. Chris Gardner, HollywoodReporter, 2 Sep. 2026 After eventually being transferred to a nearby hospital, the resident was diagnosed with sepsis and toxic epidermal necrolysis, a rare and life-threatening skin condition which causes a person’s skin to blister. Matan Josephy, Idaho Statesman, 31 Aug. 2026 At least three children died from sepsis caused by common infections that antibiotics can easily stop. Audrey Dutton, ProPublica, 25 Aug. 2026 See All Example Sentences for sepsis

Word History

Etymology

New Latin, from Greek sēpsis decay, from sēpein to putrefy

First Known Use

1863, in the meaning defined above

Time Traveler
The first known use of sepsis was in 1863

Browse Nearby Words

Cite this Entry

“Sepsis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sepsis. Accessed 7 Sep. 2026.

Medical Definition

: a potentially life-threatening, systemic response of the immune system that results from the spread of pathogenic agents (as bacteria or viruses) and their toxins to the bloodstream from a localized infection (as of the lungs), that involves both inflammatory and immunosuppressive activity, and that is marked especially by fever, chills, rapid heart rate and breathing, fatigue, confusion, increased blood coagulation, hypotension, impaired microcirculation, and organ dysfunction, and that may progress to septic shock

Note: The primary cause of sepsis is pneumonia with secondary causes commonly including infections of the abdominal cavity and urinary tract.

compare multiple organ dysfunction syndrome, septicemia
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