: 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.
In March, Hilton said in a series of posts that he had been hospitalized for three weeks with an ulcer and sepsis. Marlene Lenthang, NBC news, 14 Aug. 2026 The blogger was hospitalized in March after taking flu medicine on an empty stomach, which later led him to develop an ulcer, perforation and sepsis. Kevin Dolak, HollywoodReporter, 13 Aug. 2026 In rare cases, the infection can progress to sepsis and become fatal. Angela Haupt, Time, 12 Aug. 2026 According to the Sepsis Alliance — a nonprofit dedicated to understanding the life-threatening condition that arises from an infection in the body — some patients can experience post sepsis syndrome. Madeleine Marr, Miami Herald, 10 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 18 Aug. 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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