v. at·ten·u·at·ed, at·ten·u·at·ing, at·ten·u·ates
1. To make slender, fine, or small: The drought attenuated the river to a narrow channel.
2. To reduce in force, value, amount, or degree; weaken: Medicine attenuated the fever's effect.
3. To lessen the density of; rarefy.
4. Biology To make (bacteria or viruses) less virulent.
5. Electronics To reduce (the amplitude of an electrical signal) with little or no distortion.
To become thin, weak, or fine.
1. Reduced or weakened, as in strength, value, or virulence.
2. Botany Gradually tapering to a slender point.
[Latin attenuāre, attenuāt- : ad-, ad- + tenuāre, to make thin (from tenuis, thin; see ten- in the Appendix of Indo-European roots).]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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