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(sŭb-pū′bĭk) [″ + pubes, pubic region] Beneath the pubic arch, as a ligament, or performed beneath the pubic arch.


(sŭb-rĕt′ĭ-năl) [″ + rete, a net] Beneath the retina.

sub-Saharan Africa

(sŭb″să-har′ĕn) The large region of Africa that lies south of the Sahara desert. It extends to Ethiopia from Guinea and Senegal. Common infections in this region include malaria, meningitis, tuberculosis, and HIV/AIDS.


(sŭb-skăp′ū-lăr) [″ + scapula, shoulder blade] Below the scapula.


(sŭb-sklē′răl) [″ + Gr. skleros, hard] Beneath the sclera of the eye. SYN: subsclerotic (1).


(sŭb-skrīb′ĕr) Enrollee.


(sŭb-skrĭp′shŭn) [L. subscriptas, written under] The part of a prescription that contains directions for compounding ingredients.


(sŭb-sīd′ĕns) [L. subsidere, to sink down] The gradual disappearance of symptoms or manifestations of a disease.


1. The minimum amount of something essential for life, e.g., a subsistence diet. 2. Any means of barely supporting life.


(sŭb″spē′sēz, sŭb″spē′shēz) In taxonomy, a category below a species.


(sŭb′stāj) [″ + O.Fr. estage, position] The part of the microscope below the stage by which attachments are held in place.


(sŭb′stăns) [L. substantia, being, essence, contents] 1. Material; matter. 2. Substantia. 3. A chemical or drug. 4. When used in a medicolegal context, a chemical with potential for abuse. A great variety of entities are included: alcohol, nicotine, caffeine, sedatives, hypnotics, anxiolytics, and illicit drugs such as cannabis, heroin, or methamphetamines. Almost any substance may be abused even though its clinical use is approved when used as prescribed.

anterior perforated s. The portion of the rhinencephalon lying immediately anterior to the optic chiasm. It is perforated by numerous small arteries.

chromophilic s. A substance found in the cytoplasm of certain cells that stains similar to chromatin with basic dyes. It includes Nissl bodies of neurons and granules in serozymogenic cells.

colloid s. A jelly-like substance in colloid degeneration.

ground s. The matrix or intercellular substance in which the cells of an organ or tissue are embedded.

high threshold s. A substance such as glucose or sodium chloride present in the blood and excreted by the kidney only when its concentration exceeds a certain level.

ketogenic s. A substance that, in its metabolism, gives rise to ketone bodies.

low threshold s. A substance such as urea ...

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