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definitions

backseat driver

noun
  1. an automobile passenger who offers the driver unsolicited advice, warnings, criticism, etc., especially from the backseat.
  2. any person who, by means of criticism, unsolicited advice, or the like, interferes in affairs that are not his or her concern or responsibility.

Origin of backseat driver

First recorded in 1925–30
Related formsbackseat driving, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for back-seat driver

back-seat driver

noun informal
  1. a passenger in a car who offers unwanted advice to the driver
  2. a person who offers advice on or tries to direct matters that are not his or her concern
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
Idioms and Phrases with back-seat driver

backseat driver

A passenger who gives unwanted and/or unneeded directions to the driver; also, a person who interferes in affairs without having knowledge, responsibility, or authority for doing so. For example, Aunt Mary drives us all crazy with her instructions; she's an incurable backseat driver. This term originated in the United States in the 1920s, when it was first used for a passenger legitimately directing a chauffeur, and it was quickly transferred to figurative use. Also see the synonym Monday-morning quarterback and the antonym take a back seat.

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