sepsis

noun

sep·​sis ˈsep-səs 

plural sepses ˈsep-ˌsēz 

: 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

In those cases, staph can lead to blood infections, pneumonia, heart failure or stroke, or bone and joint infection and life-threatening conditions like sepsis and septic shock. —Saman Shafiq, USA Today, 13 May 2026

But Epic’s competition is growing as more startups test their own sepsis models in health systems. —Theresa Gaffney, STAT, 12 May 2026

Months later, Shaknovsky was alleged to have failed to recognize signs of sepsis after abdominal surgery, leading to a woman’s death in August 2023, according to an ongoing lawsuit her son filed in October 2025. —Matt Lavietes, NBC news, 7 May 2026

The suit alleged in court records that since 2011, at least 72 people died under the care of Armor Correctional Health Services after they were not hospitalized or their hospitalization was delayed, including 11 other people who died from pneumonia or sepsis. —Nichole Manna, ProPublica, 28 Apr. 2026

Word History

Etymology

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

First Known Use

1863, in the meaning defined above

Rhymes for sepsis

• antisepsis
• asepsis

Medical Definition

sepsis

noun

sep·​sis ˈsep-səs 

plural sepses ˈsep-ˌsēz 

: 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