attenuate

v. become thin or less; diminish in intensity, decrease, reduce severity

Attenuation is the reduction in amplitude and intensity of a signal. Signals may be attenuated exponentially by transmission through a medium, in which case attenuation is usually reported in dB with respect to distance traveled through the medium. Attenuation can also be understood to be the opposite of amplification. Attenuation is an important property in telecommunications and ultrasound applications because of its importance in determining signal strength as a function of distance. Attenuation is usually measured in units of decibels per unit length of medium (dB/cm, dB/km, etc) and is represented by the attenuation coefficient of the medium in question.
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Verb
1. weaken the consistency of (a chemical substance)
(synonym) rarefy
(hypernym) weaken
(derivation) attenuation
(classification) chemistry, chemical science
2. become weaker, in strength, value, or magnitude
(hypernym) weaken
(hyponym) refine
(derivation) attenuation, fading
Adjective
1. reduced in strength; "the faded tones of an old recording"
(synonym) attenuated, faded, weakened
(similar) decreased, reduced

v. attenuate, tone down, mitigate, soften, dull, understate; dilute; muffle, silence or lessen a sound

adj. muffled, reduced, lessened, decreased, diminished, weakened

(v. t.)
To make thin or slender, as by mechanical or chemical action upon inanimate objects, or by the effects of starvation, disease, etc., upon living bodies.
  

(v. t.)
To make thin or less consistent; to render less viscid or dense; to rarefy. Specifically: To subtilize, as the humors of the body, or to break them into finer parts.
  

(v. t.)
To lessen the amount, force, or value of; to make less complex; to weaken.
  

(v. i.)
To become thin, slender, or fine; to grow less; to lessen.
  

(a.)
Alt. of Attenuated