When traveling together the person sitting shotgun can be the designated navigator. Anyone sitting in the back seat is nagging and not really a 'Back Seat Driver" , making them simply an irritating "naggigator."
Also, when the actual Navigator repeats themselves too many times they are Naggigating.
Please...Stop naggigating! I heard you the first time! And Fred...in the back..who designated YOU as a Naggigator?
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