| LVCS | low vertical cesarean section |
|---|---|
| OVD | occlusal vertical dimension |
| PVD | patient very disturbed; peripheral vascular disease; portal vein dilation; posterior vitreous detach... |
| VBG | vagotomy and Billroth gastroenterostomy; venous blood gases; venous bypass graft; vertical-banded ga... |
| VPO | velopharyngeal opening; vertical pendular oscillation |
| focal illumination | Illumination in which a beam of light is directed diagonally to an object so that it is brilliantly illuminated while the surrounding area is in shadow. Synonym: lateral illumination, oblique illumination. Kohler illumination, a method of illumination of microscopic objects in which the image of the light source is focused on the substage condenser diaphragm and the diaphragm of the light source is focused in the same plane with the object to be observed; maximises both the brightness and uniformity of the illuminated field. (05 Mar 2000) |
|---|---|
| lateral illumination | Illumination in which a beam of light is directed diagonally to an object so that it is brilliantly illuminated while the surrounding area is in shadow. Synonym: lateral illumination, oblique illumination. Kohler illumination, a method of illumination of microscopic objects in which the image of the light source is focused on the substage condenser diaphragm and the diaphragm of the light source is focused in the same plane with the object to be observed; maximises both the brightness and uniformity of the illuminated field. (05 Mar 2000) |
| vertical | 1. Of or pertaining to the vertex; situated at the vertex, or highest point; directly overhead, or in the zenith; perpendicularly above one. "Charity . . . Is the vertical top of all religion." (Jer. Taylor) 2. Perpendicular to the plane of the horizon; upright; plumb; as, a vertical line. <astronomy> Vertical angle, an angle measured on a vertical circle, called an angle of elevation, or altitude, when reckoned from the horizon upward, and of depression when downward below the horizon. <botany> Vertical anthers The plane passing through the point of sight, and perpendicular to the ground plane, and also to the picture. Vertical sash, a sash sliding up and down. Cf. French sash, under 3d Sash. Vertical steam engine, a steam engine having the crank shaft vertically above or below a vertical cylinder. Origin: Cf. F. Vertical. See Vertex. 1. Vertical position; zenith. 2. <mathematics> A vertical line, plane, or circle. Prime vertical, Prime vertical dial. See Prime. Source: Websters Dictionary (01 Mar 1998) |
| vertical axis | In dentistry, the line around which the working side condyle rotates in the horizontal plane during mandibular movement. (05 Mar 2000) |
| vertical classification | <zoology> Classification which stresses common descent and tends to unite ancestral and descendant groups of a phyletic line in a single higher taxon, separating them from contemporaneous taxa having reached a similar grade of evolutionary change. Compare: Horizontal classification. (09 Jan 1998) |
| vertical dimension | The length of the face determined by the distance of separation of jaws. Occlusal vertical dimension (ovd or vdo) or contact vertical dimension is the lower face height with the teeth in centric occlusion. Rest vertical dimension (vdr) is the lower face height measured from a chin point to a point just below the nose, with the mandible in rest position. (12 Dec 1998) |
| vertical displacement event | Disruption which occurs because plasma is not adequately stabilised against vertical motions. (09 Oct 1997) |
| vertical elastic | Elastic material used in a direction perpendicular to the occlusal plane, connecting one arch wire to the other, and usually used to improve intercuspation. (05 Mar 2000) |
| vertical growth phase | Spread of melanoma cells from the epidermis into the dermis and later the subcutis, from which site metastasis may take place. (05 Mar 2000) |
| vertical heart | Loosely descriptive of the heart's electrical axis when this is directed at approximately +90 |
| vertical hymen | A hymen in which the opening is perpendicular. (05 Mar 2000) |
| vertical index | The relation of the height to the length of the skull: (height × 100)/length. Synonym: height-length index, length-height index, transversovertical index. (05 Mar 2000) |
| vertical instability | <radiobiology> A type of magnetohydrodynamic (n=0) instability where the plasma drifts vertically upward. Nearly all tokamaks are vertically unstable (all highly shaped ones are). Controlling this instability is possible in many cases, and is an important facet of machine design. Vertical instabilities give rise to halo effects. (09 Oct 1997) |
| vertical muscle of tongue | An intrinsic muscle of the tongue, consisting of fibres that pass from the aponeurosis of the dorsum to the aponeurosis of the inferior surface; action, decreases the superior to inferior dimension of (flattens) the tongue; nerve supply, hypoglossal for motor, lingual for sensory. Synonym: musculus verticalis linguae. (05 Mar 2000) |
| vertical nystagmus | An up-and-down oscillation of the eyes. (05 Mar 2000) |