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

Though most people with pneumonia, an inflammation of the lungs usually caused by infection, won’t develop sepsis, the Sepsis Alliance states that the most common source of the condition among adults is the lungs. — Adam England, PEOPLE, 17 Sep. 2026

He was diagnosed with sepsis, blood clots in the lungs, critically low blood pressure, fast heart rate and severe malnutrition. — Grethel Aguila, Miami Herald, 16 Sep. 2026

According to the medical examiner's report, Worthy's death was caused by complications of Streptococcus pyogenes sepsis, a life-threatening bacterial infection that can lead to organ failure and shock. — Dan Raby, CBS News, 10 Sep. 2026

Still tiny, Obelix developed sepsis, an extreme reaction to infection. — Laura Sharman, CNN Money, 9 Sep. 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