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tachyphylaxis

American  
[tak-uh-fi-lak-sis] / ˌtæk ə fɪˈlæk sɪs /
Also tachyphylaxia

noun

  1. Medicine/Medical. immediate, temporary immunization against the effects of injection of a toxic extract owing to previous small injections of the same extract.

  2. a decreased response to a medicine given over a period of time so that larger doses are required to produce the same response.

tachyphylaxis British  
/ ˌtækɪfɪˈlæksɪs /

noun

  1. very rapid development of tolerance or immunity to the effects of a drug

"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

Other Word Forms

  • tachyphylactic adjective

Etymology

Origin of tachyphylaxis

tachy- + Greek phýlaxis a guarding, equivalent to phylak- (stem of phylássein to guard) + -sis -sis

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.