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defibrillator

[dee-fahy-bruh-ley-ter, -fib-ruh-]
noun Medicine/Medical.
  1. an agent or device for arresting fibrillation of the atrial or ventricular muscles of the heart.

Origin of defibrillator

First recorded in 1955–60; de- + fibrill(ation) + -ator
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for defibrillator

defibrillator

noun
  1. med an apparatus for stopping fibrillation of the heart by application of an electric current to the chest wall or directly to the heart
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 defibrillator
n.

1956, agent noun from defibrillation.

Online Etymology Dictionary, © 2010 Douglas Harper
defibrillator in Medicine

defibrillator

[dē-fĭb′rə-lā′tər, -fī′brə-]
n.
  1. An electrical device used to counteract fibrillation of the heart muscle and restore normal heartbeat by applying a brief electric shock.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.