I know the phrase means "going all out" but I can't figure out what it literally means or where it originates from.
First attested in the 1960s in the context of aviation. Probably coined by pilots whose throttle levers had round, ball-like tops and for whom putting the "balls to the wall" (the firewall of the aircraft) meant making the aircraft fly as quickly as possible.
protected by tchrist♦ Mar 31 '14 at 22:50
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