headache bar
n.— «The state is also considering the installation of a “headache bar.” That is a device that would use chains hanging from an overhead sign near the bridge to warn a trucker that his vehicle is too tall for the clearance. “Trucks would strike the chains before the bridge.”» —“Salina Residents Voice Opposition to Route 370 Changes” by Matthew Cox Post-Standard Jan. 28, 1988. (source: Double-Tongued Dictionary)
Further reading
Aubrey in Waco, Texas, says her mother used to warn the kids against contracting honkus of the bonkus, a fanciful name for a contagious disease. This colloquial term probably comes from the words bonk and konk, meaning “to hit” or...
When she was a child, Chris from Santa Rosa, California, misunderstood the definition of the word vehicle—with amusing results. This is part of a complete episode.
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