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(sēr′ŏ-sŭr″vā′) [sero- + survey] Sampling of blood in people living in a community to determine the percentage of those who have been previously exposed or susceptible to a disease, esp. an infectious disease.


(sē″rō-ther′ă-pē) [sero- + therapy] 1. Passive immunization with antivenins. SYN: serum therapy. 2. Treatment of a patient with serum. SYN: serum therapy.

serotonergic neuron

(sir″ă-tŏ-nĕr′jik) SEE: under neuron.


(sir″ŏ-tō′nĭn) [sero- + tone + -in] C10H12N2O, a vasoconstrictor found in platelets, the gastrointestinal mucosa, mast cells, carcinoid tumors, and the central nervous system. Serotonin, through its action on cellular receptors, plays important roles in intestinal motility, nausea and vomiting, sleep-wake cycles, obsessive-compulsive behaviors, depression, and eating. SYN: 5-HT; 5-hydroxytryptamine. SEE: carcinoid syndrome; selective serotonin reuptake inhibitor.

serotonin and norepinephrine reuptake inhibitor

SEE: under inhibitor.

serotonin release assay

SEE: under assay.

serotonin syndrome

The adverse effects of excessive levels of serotonin in the brain, typically caused by exposure to multiple medications that alter the neuronal disposition of serotonin. Common findings are confusion, restlessness, hyperreflexia, agitation, diaphoresis, tremor, and fever.


(sēr′ŏ-tīp″) [sero- + type] In microbiology, a microorganism distinguished from others by the unique antigens present on its cell surface.


(sēr′ŭs) [L. serosus] 1. Having the nature of serum. 2. Thin or watery, rather than syrupy, thick, or viscous.


(sēr′ō-văr″) [serological variation] Any of the variants within a species defined by variation in serological reactions. SEE: biovar; morphovar.


(sĕr-pĭj′ĭ-nŭs) [L. serpere, to creep] Creeping from one part to another.


(ser′āt″) [L. serratus, toothed] Dentate.


(se-rā′sh(ē-)ă) [Serafino Serrati, 19th-cent. Italian physicist ] A genus of gram-negative bacilli of the family Enterobacteriaceae.

S. liquefaciens A species that has caused septicemia and other hospital-acquired infections.

S. marcescens An opportunistic bacterium that causes septicemia and pulmonary disease, esp. in immunocompromised patients, and is found in water, soil, milk, and stools. In the proper environment, the organism will grow on food and produce the red pigment prodigiosin.


(sĕ-rā′shŏn) [L. serratio, a notching] 1. A formation with sharp projections like the teeth of a saw. 2. A single tooth or notch in a serrated edge.



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