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

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

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