[ verb uh-ten-yoo-eyt; adjective uh-ten-yoo-it, -eyt ]
/ verb əˈtɛn yuˌeɪt; adjective əˈtɛn yu ɪt, -ˌeɪt /

verb (used with object), at·ten·u·at·ed, at·ten·u·at·ing.

verb (used without object), at·ten·u·at·ed, at·ten·u·at·ing.

to become thin or fine; lessen.


weakened; diminishing.
Botany. tapering gradually to a narrow extremity.

Nearby words

  1. attentive,
  2. attentively,
  3. attentiveness,
  4. attently,
  5. attenuant,
  6. attenuated,
  7. attenuated virus,
  8. attenuation,
  9. attenuator,
  10. attercop

Origin of attenuate

First recorded in 1520–30, attenuate is from the Latin word attenuātus (past participle of attenuāre to thin, reduce). See at-, tenuis, -ate1

Related forms Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for attenuating

British Dictionary definitions for attenuating


verb (əˈtɛnjʊˌeɪt)

to weaken or become weak; reduce in size, strength, density, or value
to make or become thin or fine; extend
(tr) to make (a pathogenic bacterium, virus, etc) less virulent, as by culture in special media or exposure to heat

adjective (əˈtɛnjʊɪt, -ˌeɪt)

diluted, weakened, slender, or reduced
botany tapering gradually to a point

Word Origin for attenuate

C16: from Latin attenuāre to weaken, from tenuis thin

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for attenuating



"to make thin, to make less," 1520s, from Latin attenuatus "enfeebled, weak," past participle of attenuare "to make thin, lessen, diminish," from ad- "to" (see ad-) + tenuare "make thin," from tenuis "thin" (see tenet). Related: Attenuated; attenuating. Earlier was Middle English attenuen "to make thin (in consistency)," early 15c.

Online Etymology Dictionary, © 2010 Douglas Harper

Medicine definitions for attenuating


[ ə-tĕnyōō-āt′ ]


To reduce in force, value, amount, or degree; weaken; diminish.
To make bacteria or viruses less virulent.


Reduced or weakened, as in strength, value, or virulence.

The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.