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special needs child

A child who is protected by governmental agencies and made ready for adoption after abandonment, abuse, or neglect in his or her home. SYN: waiting child.


(spesh′ăl-tē) The branch of medicine, surgery, dentistry, or nursing in which a specialist practices.

specialty hospital

SEE: under hospital.


(spē″sē-ā′shŏn, spē″shē-ā′shŏn) 1. The evolutionary process by which new species of living organisms are formed. 2. The identification of the species of an organism, e.g., of an infectious bacterium.

sympatric s. Divergence of two related species from a common local ancestor.


(spē′s(h)ēz″) [L. species, a kind] ABBR: sp. In biology, a category of classification for living organisms just below the genus. Members of a species are usually capable of interbreeding.


The characteristics of a species, esp. the immunological nature that differentiates that species from another.


(spĕ-sif′ik) [L. specificus, pert. to a kind] 1. Pert. to a remedy that has a curative effect on a particular disease or symptom. 2. Pert. to a species. 3. Pert. to a disease that is always caused by the same organism. 4. Restricted, explicit; not generalized.

specific dynamic action of food

Thermic effect of food.

specific gravity

ABBR: sp. gr. The mass of a substance compared with the mass of an equal volume of water. For solid and liquid materials, water is used as a standard and considered to have a specific gravity of 1.000. For gases, the weight per unit volume is compared with that of dry air at a specified temperature and usually at atmospheric pressure. SYN: relative density.


(spes″ĭ-fis′ĭt-ē) 1. The state of being specific; having a relation to a definite result or to a particular cause. 2. The ability of a test to exclude those who are truly free of a disease or condition. It is a test that reports negative when the characteristic looked for is absent.

antigenic s. The property of mature B and T lymphocytes that enables them to respond to specific foreign antigens entering the body. Antigen specificity requires mature B and T cells that have been previously exposed to the antigen and, therefore, are able to recognize it again and respond by neutralizing or destroying it. The exact process by which B lymphocytes become capable of recognizing and responding to antigens is unknown. Development of antigen specificity by T cells requires macrophage processing of the antigen for recognition.

diagnostic s. For a diagnostic or screening test, the proportion of people ...

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