backseat driver

UK: /ˈbæksiːt/ US: /ˈbækˌsit ˈdraɪvɚ/

WordReference Random House Learner's Dictionary of American English © 2025

back•seat driv•er /ˈbækˌsit ˈdraɪvɚ/  n. [countable]

1. an automobile passenger who offers the driver directions, instructions, advice, or criticism that are not asked for.

WordReference Random House Unabridged Dictionary of American English © 2025

back′seat driv′er, 

1. an automobile passenger who offers the driver unsolicited advice, warnings, criticism, etc., esp. 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.
• 1925–30
back′seat driv′ing. 

Collins Concise English Dictionary © HarperCollins Publishers::

back-seat driver noun

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