1. <cell biology> The adjustment of an organism to its environment or the process by which it enhances such fitness.
2. The normal ability of the eye to adjust itself to variations in the intensity of light, the adjustment to such variations.
3. <neurology, physiology> The decline in the frequency of firing of a neuron, particularly of a receptor, under conditions of constant stimulation.
4. <dentistry> (a) the proper fitting of a denture, (b) the degree of proximity and interlocking of restorative material to a tooth preparation, (c) the exact adjustment of bands to teeth.
5. <microbiology> The adjustment of bacterial physiology to a new environment.
Origin: L. Adaptare = to fit
(18 Nov 1997)