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definitions

panic bar

noun
  1. a bar that spans an emergency exit door on its interior and opens the latch when pressure is applied.

Origin of panic bar

First recorded in 1925–30
Also called panic bolt.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for panic bolt

panic bolt

noun
  1. a bolt on the inside esp of double doors that is released by pressure on a waist-high bar: used for emergency exits in theatres, shops, etc
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