| molar tooth | A tooth having a somewhat quadrangular crown with four or five cusps on the grinding surface; the root is bifid in the lower jaw, but there are three conical roots in the upper jaw; there are six molars in each jaw, three on either side behind the premolars in the permanent dentition; in the deciduous dentition there are but four molars in each jaw, two on either side behind the canines. Synonym: dens molaris, cheek tooth, molar, multicuspid tooth. (05 Mar 2000) |
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| mulberry molar | A molar tooth with alternating nonanatomical depressions and rounded enamel nodules on its crown surface, usually associated with congenital syphilis. (05 Mar 2000) |
| second molar | Seventh permanent or fifth deciduous tooth in the maxilla and mandible on either side of the midsagittal plane of the head following the arch form. (05 Mar 2000) |
| sixth-year molar | The first permanent molar tooth. (05 Mar 2000) |
| third molar | Eighth permanent tooth in the maxilla and mandible on each side, making it the most posterior tooth in human dentition; usually erupts between the seventeenth and twenty-third years; the roots are often fused, the separation being marked only by grooves; because it tends to erupt in an anterosuperior direction, the lower third molar often becomes impacted against the lower second molar; it is common for one or more third molar to fail to develop. Synonym: dens serotinus, molaris tertius, dens sapientiae, wisdom tooth. (05 Mar 2000) |
| twelfth-year molar | The second permanent molar tooth. (05 Mar 2000) |
| first molar | First permanent molar, sixth permanent tooth or fourth deciduous tooth in the maxilla and mandible on either side of the midsagittal plane of the head following the arch form. (05 Mar 2000) |
| 12 year molar | <dentistry> Another name for your second molar (05 Mar 2000) |
| 6 year molar | <dentistry> Another name for your first molar (05 Mar 2000) |
| absorption | The process of absorbing, specifically: 1. <physiology> The movement and uptake of substances (liquids and solutes) into cells or across tissues such as skin, intestine and kiidney tubules, by way of diffusion or osmosis. 2. <chemistry> The drawing of a gas or liquid into the pores of a permeable solid. 3. <psychology> The devotion of thought to one object or activity, with inattention to others. 4. <radiology> The taking up of energy by matter with which the radiation interacts. 5. <physics> The loss of (electromagnetic) energy to a medium. For instance, an electromagnetic wave which propagates through a plasma will set the electrons into motion. If the electrons make collisions with other particles, they will absorb net energy from the wave. 6. <immunology> A process in which an antigen or antibody is used to pull an analogous antigen or antibody out of a solution. Compare: adsorption. Origin: L. Absorptio (12 Nov 1997) |
| absorption band | The range of wavelengths or frequencies in the electromagnetic spectrum where radiant energy is absorbed by passage through a gaseous, liquid, or dissolved substance; it is exploited for analytical purposes in colourimetry or spectrophotometry, and is usually described in terms of the wavelength where maximum absorbance occurs (i.e., lambdamax). (05 Mar 2000) |
| absorption cell | A small glass chamber with parallel sides, in which absorption spectra of solutions can be obtained. (05 Mar 2000) |
| absorption chromatography | <investigation> Techniques for separating molecules based on differential absorption and elution. Term for separation methods involving flow of a fluid carrier over a nonmobile absorbing phase. (18 Nov 1997) |
| absorption collapse | Pulmonary collapse due to rapid complete obstruction of a large bronchus. (05 Mar 2000) |
| absorption fever | An elevation of temperature often occurring, without other untoward symptoms, shortly after childbirth, assumed to be due to absorption of uterine discharges through abrasions of the vaginal wall. (05 Mar 2000) |