[dee-fahy-bruh-leyt, -fib-ruh-]
verb (used with object), de·fi·bril·lat·ed, de·fi·bril·lat·ing. Medicine/Medical.
  1. to arrest the fibrillation of (heart muscle) by applying electric shock across the chest, thus depolarizing the heart cells and allowing normal rhythm to return.

Origin of defibrillate

1930–35; de- + fibrillate, back formation from fibrillation
Related formsde·fi·bril·la·tion, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for defibrillation


  1. med the application of an electric current to the heart to restore normal rhythmic contractions after the onset of atrial or ventricular fibrillation
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 defibrillation

1940, in reference to heartbeat, from de- + fibrillation "a beating in an abnormal way," from Modern Latin fibrilla, diminutive of fibra "fiber," in reference to the muscle strands of the heart that contract irregularly in this condition.

Online Etymology Dictionary, © 2010 Douglas Harper

defibrillation in Medicine


[dē-fĭb′rə-lāshən, -fī′brə-]
  1. The stopping of fibrillation of the heart muscle and the restoration of normal contractions using drugs or electric shock.
Related formsde•fibril•late′ v.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

defibrillation in Science


  1. Termination of fibrillation of the heart muscle and restoration of normal heart rhythm, especially by one or more electric shocks administered by paddles applied to the chest.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.