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

Along with sepsis, his cause of death was hypothermia. —USA Today, 8 Mar. 2026

The massive health records company Epic Systems rolled out a tool that claimed to be able to predict sepsis. —Emily Brindley, Chicago Tribune, 5 Mar. 2026

The child had contracted Haemophilus influenzae type b, a nasty bacterial illness that can cause mild symptoms in some children, but triggers dangerous, more systemic disease in others — things like meningitis, pneumonia, and sepsis. —Helen Branswell, STAT, 2 Mar. 2026

So many women die of urinary sepsis and bacteremia that has come from a UTI. —Tribune News Service, Baltimore Sun, 2 Mar. 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