'attenuate' definitions:

Definition of 'attenuate'

(from WordNet)
adjective
Reduced in strength; "the faded tones of an old recording" [syn: attenuate, attenuated, faded, weakened]
verb
Weaken the consistency of (a chemical substance) [syn: rarefy, attenuate]
verb
Become weaker, in strength, value, or magnitude