wave (redirected from Wave (the earth sciences))

wave (wāv) 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

Etymology: AS, wafian, to fluctuate

a periodic disturbance in which energy moves through a medium without permanently altering the constituents of the medium. Electromagnetic waves, such as light, x-rays, and radio waves, can travel through a vacuum. Sound waves can be transmitted only through matter. See also electromagnetic radiation, light, sound, x-ray.

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wave [wāv]

1. a uniformly advancing disturbance in which the parts undergo a change in direction, such as a progressing disturbance on the surface of a liquid.

2. variation in the transmission of electromagnetic energy, especially the periodic change in direction of a reading on a monitoring device.

A wave the wave on a His bundle electrogram that represents atrial activation.

alpha w's brain waves having a frequency of 8 to 13 per second, typical of a normal person awake in a quiet resting state; they occur primarily in the occipital region.

B wave a sharp rhythmic oscillation with a sawtooth pattern, occurring every 30 seconds to two minutes during intracranial pressure monitoring, associated with unstable increases in pressure.

beta w's brain waves having a frequency of 18 to 30 per second, typical during periods of intense central nervous system activity; they occur primarily in the parietal and frontal regions.

brain w's changes in electric potential of different areas of the brain, as recorded by electroencephalography. See also alpha, beta, delta, and theta waves.

C wave in intracranial pressure monitoring, a small rhythmic oscillation in pressure that occurs every four to eight minutes.

delta w's

1. brain waves having a frequency below 3½ per second, typical in deep sleep, in infancy, and in serious brain disorders.

2. an early QRS vector in the electrocardium in wolff-parkinson-white syndrome.

dicrotic wave the second portion of the tracing of a sphygmograph of the arterial pulse or arterial pressure after the dicrotic notch, attributed to the reflected impulse of closure of the aortic valves. Called also recoil wave

electromagnetic w's the entire series of ethereal waves, which are similar in character and move at the speed of light but vary enormously in wavelength. The unbroken series is known from radio waves that may be many kilometers in length through light waves, ultraviolet rays, x-rays, and gamma rays, to the cosmic rays, whose wavelength may be as short as 40 femtometers (4 × 10⁻¹⁴ m).

light w's the electromagnetic waves that produce sensations on the retina; see also vision.

P wave a positive deflection in the normal surface electrocardiogram produced by the wave of excitation passing over the atria; it represents atrial depolarization, an intrinsic atrial event.

papillary wave (percussion wave) the chief ascending portion of the tracing of a sphygmograph.

plateau wave a wave seen during intracranial pressure monitoring in advanced stages of increased pressure, signaling hypoxia of the brain cells.

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.

QRS wave QRS complex.

R wave in the normal surface electrocardiogram, the initial upward deflection of the QRS complex, following the Q wave; it represents ventricular depolarization. In cardiac pacing, it may be the entire native or intrinsic QRS complex.

radio w's electromagnetic waves of wavelength between 10⁻¹ and 10⁶ cm and frequency of about 10¹¹ to 10⁴ hertz.

recoil wave dicrotic wave.

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

sonic w's audible sound waves.

sound w's longitudinal waves of mechanical energy that transmit the vibrations interpreted as sound (def. 2).

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

theta w's brain waves having a frequency of 4 to 7 per second, occurring mainly in children but also seen in adults under emotional stress.

tidal wave the wave after the percussion wave on a sphygmograph recording; the second elevation of the tracing, preceding the dicrotic wave.

ultrasonic w's waves similar to sonic waves but of such high frequency (20,000 hertz or higher) that the human ear does not perceive them as sound; see ultrasonics.

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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.

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wave

Medtalk A continuous, uniformly advancing oscillation about a “zero” point; a wavelike pattern. See A wave, Alpha wave, Blood pressure wave, Body wave, Brain wave, C wave, Cannon 'a' wave, ' Compression wave, Delta wave, F wave, Fluid wave, H wave, Heat wave, Herald wave, J wave, Lambda wave, M wave, P wave, Pontine-geniculate-occipital wave, Q wave, R wave, S wave, Sine wave, Slow wave, Square wave, T wave, Theta wave, U wave, V wave, Zigzag QRS wave.

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Patient discussion about wave.

Q. What kind of depression is characterized by waves? It's not a constant depression, like if you can be happy but then you feel the depression creeping up on you, like a wave, lasts for a few to several days/weeks? Is there even a name for it?

A. When depression is serious enough to require treatment, it is called clinical depression. When the symptoms are more severe, someone is said to be suffering from major depression. This condition tends to be episodic in nature. In that case – there is a treatment that can help preventing that! go to a psychiatrist.