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definitions

automatic transmission

noun
  1. an automotive transmission requiring either very little or no manual shifting of gears.

Origin of automatic transmission

First recorded in 1945–50
Also called automatic, automatic drive.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for automatic drive

automatic transmission

noun
  1. a transmission system in a motor vehicle, usually incorporating a fluid clutch, in which the gears change automatically
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