wave (redirected from WAVES)

wave (wav) a uniformly advancing disturbance in which the parts moved undergo a double oscillation; any wavelike pattern.

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alpha waves  see under rhythm.

beta waves  see under rhythm.

brain waves  the fluctuations of electric potential in the brain, as recorded by electroencephalography.

delta wave 

1. an early QRS vector in the electrocardiogram in preexcitation.

2. (pl.) electroencephalographic waves with a frequency below 3.5 per second, typical in deep sleep, infancy, and serious brain disorders.

electromagnetic waves  the spectrum of waves propagated by an electromagnetic field, having a velocity of 3 × 108 m/s in a vacuum and including, in order of decreasing wavelength, radio waves, microwaves, infrared, visible, and ultraviolet light, x-rays, gamma rays, and cosmic rays.

Diagrammatic representation of electromagnetic waves.

F waves 

1. flutter w's; rapid sawtooth-edged atrial waves without isoelectric intervals between them; seen in the electrocardiogram in atrial flutter. Written also f w's .

2. f w's (1).

f waves 

1. fibrillary w's; small, irregular, rapid deflections in the electrocardiogram in atrial fibrillation. Written also F w's.

2. F w's (1).

fibrillary waves  f w's (1).

flutter waves  F w's (1).

J wave  a deflection occurring in the electrocardiogram between the QRS complex and the onset of the ST segment, occurring prominently in hypothermia and in hypocalcemia.

P wave  a deflection in the electrocardiogram produced by excitation of the atria.

pulse wave  the elevation of the pulse felt by the finger or shown graphically in a recording of pulse pressure.

Q wave  in the QRS complex, the initial downward (negative) deflection, related to the initial phase of depolarization of the ventricular myocardium, the depolarization of the interventricular septum.

R wave  the initial upward deflection of the QRS complex, following the Q wave in the normal electrocardiogram and representing early depolarization of the ventricles.

S wave  a downward deflection of the QRS complex following the R wave in the normal electrocardiogram and representing late depolarization of the ventricles.

T wave  the deflection of the normal electrocardiogram following the QRS complex; it represents repolarization or recovery of the ventricles.

Ta wave  a small asymmetric wave, of opposite polarity to the P wave, representing atrial repolarization; together with the P wave it defines atrial systole.

theta waves  brain waves in the electroencephalogram with a frequency of 4 to 7 per second, mainly seen in children and emotionally stressed adults.

U wave  a potential undulation of unknown origin immediately following the T wave and often concealed by it; seen in the normal electrocardiogram and accentuated in tachyarrhythmias and electrolyte disturbances.

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wave (wv)

n.

1. A disturbance traveling through a medium by which energy is transferred from one particle of the medium to another without causing any permanent displacement of the medium itself.

2. A graphic representation of the variation of such a disturbance with time.

3. A single cycle that is representative of such a disturbance.

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wave

a uniformly advancing disturbance in which the parts undergo a double oscillation, as a progressing disturbance on the surface of a liquid or the rhythmic variation occurring in the transmission of electromagnetic energy.

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brain w's

changes in electric potential of different areas of the brain, as recorded by electroencephalography.

electromagnetic w's

the entire series of ethereal waves which are similar in character, and which move with the velocity of light, but which vary enormously in wavelength. The unbroken series is known from the hertzian waves used in radio transmission, which may be miles in length (one mile equals 1.6 × 10⁵ cm), through heat and light, the ultraviolet, x-rays, and gamma rays of radium to the cosmic rays, the wavelength of which may be as short as 40 femtometers (4 × 10^-14 nm).

wave F

1. a muscle action potential seen on electromyographs; attributed to antidromically conducted motor nerve action potentials.

2. bidirectional, saw-toothed waves on an electrocardiographic tracing characteristic of atrial flutter.

light w's

the electromagnetic waves that produce sensations on the retina. See also vision.

wave motion

swirling motion in a drop of dense semen when viewed microscopically (100 × magnification). The intensity and rapidity of the swirling is a reflection of the concentration of the spermatozoa and their level of motility. Called also mass activity.

P wave

a deflection in the normal electrocardiogram produced by the wave of excitation passing over the atria.

positive sharp wave

an electromyographic tracing associated with denervation and some types of primary muscle disease.

pulse wave

the elevation of the pulse felt by the finger or shown graphically in a recording of pulse pressure.

Q wave

in the QRS complex, the initial electrocardiographic downward (negative) deflection, related to the initial phase of depolarization.

R wave

the initial upward deflection of the QRS complex, following the Q wave in the normal electrocardiogram.

S wave

a downward deflection of the QRS complex following the R wave in the normal electrocardiogram.

T wave

the second major deflection of the normal electrocardiogram, reflecting the potential variations occurring with repolarization of the ventricles.

T wave abnormalities

a common finding in horses whose racing performance worsens. The cause is not identified but may be related to overtraining and the racing of unfit horses. Most animals recover spontaneously with rest. The validity of these abnormalities is now widely doubted.