sepsis

noun

sep·​sis ˈsep-səs How to pronounce sepsis (audio)
plural sepses ˈsep-ˌsēz How to pronounce sepsis (audio)
: 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.
Patients with pneumonia might face complications, including sepsis or bacteria in the bloodstream, difficulty breathing, fluid around the lungs and abscesses in the lungs. Rebecca Cohen, NBC news, 16 Oct. 2025 The university’s recent efforts in using real-time analysis of digital medical records to predict sepsis, a deadly blood infection, in emergency department patients have garnered significant national attention. Paul Sisson, San Diego Union-Tribune, 16 Oct. 2025 Rushed to the Shahjahanpur Medical College, she was found to have a severe infection, respiratory distress, injuries, and sepsis. Aishwarya S. Iyer, CNN Money, 16 Oct. 2025 These are often the most severe bacterial infections—resulting in sepsis, organ failure and death if not treated properly or effectively. Hannah Millington, MSNBC Newsweek, 14 Oct. 2025 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 22 Oct. 2025.

Medical Definition

sepsis

noun
sep·​sis ˈsep-səs How to pronounce sepsis (audio)
plural sepses ˈsep-ˌsēz How to pronounce sepsis (audio)
: 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
Last Updated: - Updated example sentences
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