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.
Meningitis can spread easily and cause brain swelling, sepsis, loss of hearing or limbs, and death. Isabella Cueto, STAT, 6 Jan. 2026 Surgeons noted her injuries included three perforations of the small bowel and sepsis. Jason Kane, NBC news, 31 Dec. 2025 Left untreated, sepsis can lead to death. Fred Schulte, Miami Herald, 30 Dec. 2025 In April 2024, the artist and Church of Latter-day Saints influencer shared on Instagram that her 9-year-old daughter, Abigail Carlton, had unexpectedly died from sepsis. Emily Blackwood, PEOPLE, 29 Dec. 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 12 Jan. 2026.

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
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!