verb at·ten·u·ate \ ə-ˈten-yə-ˌwāt , -yü-ˌāt \
|Updated on: 12 Jul 2018

Definition of attenuate

attenuated; attenuating
1 : to lessen the amount, force, magnitude, or value of : weaken
  • … shows great skill in the use of language to moderate or attenuate the impact of awkward facts.
  • —Bernard Lewis
2 : to reduce the severity, virulence, or vitality of
  • an attenuated virus
3 : to make thin or slender
  • Glass can be attenuated into fibers.
4 : to make thin in consistency : rarefy
  • attenuate oil by heating it
: to become thin, fine, or less


\ə-ˌten-yə-ˈwā-shən, -yü-ˈā-\ noun

attenuate was our Word of the Day on 06/29/2016. Hear the podcast!

Examples of attenuate in a Sentence

  1. Earplugs will attenuate the loud sounds of the machinery.

  2. an investment attenuated by significant inflation over the years

Recent Examples of attenuate from the Web

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Origin and Etymology of attenuate



adjective at·ten·u·ate \ ə-ˈten-yə-wət , -yü-ət \

Definition of attenuate

1 : reduced especially in thickness, density, or force
  • the attenuate limbs of a starving person
2 : tapering gradually usually to a long slender point
  • attenuate leaves

Did You Know?

Attenuate ultimately comes from a combination of the Latin prefix ad-, meaning "to" or "toward," and tenuis, meaning "thin." It has been on the medical scene since the 16th century, when a health treatise recommended eating dried figs to attenuate bodily fluids. That treatment might be outmoded nowadays, but attenuate is still used in medicine to refer to procedures that weaken a pathogen or reduce the severity of a disease. Most often, though, attenuate implies that something has been reduced or weakened by physical or chemical means. You can attenuate wire by drawing it through successively smaller holes, or attenuate gold by hammering it into thin sheets. You can even attenuate the momentum of a play by including too many costume changes.

Origin and Etymology of attenuate

Middle English attenuat, from Latin attenuatus, past participle of attenuare to make thin, from ad- + tenuis thin — more at thin

ATTENUATE Defined for English Language Learners


Definition of attenuate for English Language Learners

  • : to make (something) weaker or less in amount, effect, or force

Medical Dictionary


transitive verb at·ten·u·ate \ ə-ˈten-yə-ˌwāt \

medical Definition of attenuate

attenuated; attenuating
: to reduce the severity of (a disease) or virulence or vitality of (a pathogenic agent)
  • a procedure to attenuate severe diabetes
  • attenuated bacilli

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