| total quality management | The application of industrial management practice to systematically maintain and improve organization-wide performance. Effectiveness and success are determined and assessed by quantitative quality measures. (12 Dec 1998) |
|---|---|
| total refractory period | The absolute refractory period plus the relative refractory period. (05 Mar 2000) |
| total sclerectasia | Uniform stretching of the entire sclera, typically seen in buphthalmos. (05 Mar 2000) |
| total spinal anaesthesia | Spinal anaesthesia extensive enough to produce loss of sensation in all extracranial sensory roots. (05 Mar 2000) |
| total suspended particulates | The quantity of solid particles in a gas or exhaust stream. Any finely divided material (solid or liquid) that is airborne with a diameter smaller than a few hundred micrometres. (05 Dec 1998) |
| total suspended solids | The organic and inorganic material left on a standard glass fibre filter (0.45 micron) after a water sample is filtered through it. (09 Oct 1997) |
| total synechia | Adhesion of the entire surface of the iris to the lens capsule. (05 Mar 2000) |
| total transfusion | Removal of most of a patient's blood followed by introduction of an equal amount from donors. Synonym: exsanguination transfusion, substitution transfusion, total transfusion. (05 Mar 2000) |
| achromatic lens | A compound lens made of two or more lens's having different indices of refraction, so correlated as to minimise chromatic aberration. (05 Mar 2000) |
| acoustic lens | In ultrasonography, a lens used to focus or diverge a sound beam; may be simulated by electronic manipulation of signals. (05 Mar 2000) |
| anterior pole of lens | The central point on the anterior surface of the lens of the eye. Synonym: polus anterior lentis. (05 Mar 2000) |
| anterior surface of lens | The anterior surface of the lens of the eye. Synonym: facies anterior lentis. (05 Mar 2000) |
| aplanatic lens | A lens designed to correct spherical aberration and coma (q.v.). Synonym: periscopic meniscus. (05 Mar 2000) |
| apochromatic lens | A compound lens designed to correct both spherical and chromatic aberrations. (05 Mar 2000) |
| asphenc lens | <physics> A lens made aplanatic by grinding the outer zones to a greater radius than the inner zones. Aplanatic condensers can be made in this way. A simple aspheric lens is widely used as a lamp condenser because of its efficiency in converging light rays to one focal plane. (05 Aug 1998) |