| S wave | A negative (downward) deflection of the QRS complex following an R w; successive downward deflections within the same QRS complex are labelled S', S'', etc. (05 Mar 2000) |
|---|---|
| dicrotic wave | The second rise in the tracing of a dicrotic pulse. Synonym: recoil wave. (05 Mar 2000) |
| drift wave | <radiobiology> Oscillations in a magnetically-confined plasma arising in the presence of density gradients (such as at the plasma's surface). These resemble the waves that propagate at the interface of two fluids with different density in a gravitational field. (09 Oct 1997) |
| D wave | A positive or negative deflection in the electroretinogram occurring when a light stimulus is removed (off-response). (05 Mar 2000) |
| quarter-wave plate | <microscopy> A compensator giving a retardation of about 130 nm, and a phase shift of 1/4 ~, thus constituting a device used with a polarizer and analyser designed to produce circularly polarized light. (05 Aug 1998) |
| Q wave | The initial deflection of the QRS complex when such deflection is negative (downward). (05 Mar 2000) |
| overflow wave | The descending wave of the sphygmogram from the apex to the first anacrotic break. (05 Mar 2000) |
| theta wave | Brain waves in the electroencephalogram which have a frequency of 4 to 7 per second. They occur mainly in children but also in adults during periods of emotional stress. (12 Dec 1998) |
| tidal wave | The wave between the percussion wave and the dicrotic wave in the downward limb of the arterial pulse tracing. (05 Mar 2000) |
| electrocardiographic wave | <cardiology, physiology> A deflection of special shape and extent in the electrocardiogram representing the electric activity of a portion of the heart muscle. (05 Mar 2000) |
| electrohydraulic shock wave lithotripsy | Destruction of calculi (urinary tract or other) by fragmentation using shock waves sent transcutaneously. (05 Mar 2000) |
| electromagnetic wave | <physics> A wave of electric and magnetic fields that can move through space. Particles which make up the waves are called photons. (09 Oct 1997) |
| electrostatic wave | <radiobiology> Longitudinal oscillations appearing in a plasma due to a perturbation of electric neutrality. For a cold unmagnetised plasma, or at large wavelengths, the frequency of these waves is by definition the plasma frequency. (09 Oct 1997) |
| transverse wave | <radiobiology> Waves in which the direction of the oscillation is perpendicular (transverse) to the direction of the wave propagation. Examples include plucked strings and electromagnetic waves in free space or air. (09 Oct 1997) |
| T wave | The next deflection in the electrocardiogram following the QRS complex; represents ventricular repolarization. (05 Mar 2000) |