1. The state of equilibrium (balance between opposing pressures) in the body with respect to various functions and to the chemical compositions of the fluids and tissues. 2. The processes through which such bodily equilibrium is maintained. [homeo- + G. stasis, standing]
- Bernard-Cannon h. the set of mechanisms responsible for the cybernetic adjustment of physiologic and biochemical states in postnatal life. SYN: physiologic h..
- Lerner h. the restorative mechanisms that tend to correct perturbations in the genetic composition of a population. SYN: genetic h..
- ontogenic h. SYN: homeorrhesis.
- physiologic h. SYN: Bernard-Cannon h..
- waddingtonian h. SYN: homeorrhesis.
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ho·meo·sta·sis or Brit ho·moeo·sta·sis .hō-mē-ō-'stā-səs n the maintenance of relatively stable internal physiological conditions (as body temperature or the pH of blood) in higher animals under fluctuating environmental conditions also the process of maintaining a stable psychological state in the individual under varying psychological pressures or stable social conditions in a group under varying social, environmental, or political factors
ho·meo·stat·ic or Brit ho·moeo·stat·ic -'stat-ik adj
ho·meo·stat·i·cal·ly or Brit ho·moeo·stat·i·cal·ly -i-k(ə-)lē adj
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n.
the physiological process by which the internal systems of the body (e.g. blood pressure, body temperature, acid-base balance) are maintained at equilibrium, despite variations in the external conditions.
• homeostatic adj.
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ho·meo·sta·sis (ho″me-o-staґsis) [homeo- + -stasis] a tendency to stability in the normal body states (internal environment) of the organism. It is achieved by a system of control mechanisms activated by negative feedback; e.g., a high level of carbon dioxide in extracellular fluid triggers increased pulmonary ventilation, which in turn causes a decrease in carbon dioxide concentration. See also equilibrium (def. 1). homeostatic adjMedical dictionary. 2011.