Dashboard

wiktionary

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From dash(“to sprinkle; to splatter”) +‎ board for meaning 1. Possibly expanded meaning later.

etymonline

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dashboard (n.)

also dash-board, 1846, "board or leather apron in front of a carriage to stop mud from being splashed ('dashed') into the vehicle by the horse's hoofs," from dash (v.) + board (n.1). Of motor vehicles, "panel under the windshield, on which control panels and gauges are mounted,” by 1904. Except for the situation relative to the front seat, it has nothing in common with the original.