mach diamond
n.— «Nerves jangling, he awaits the moment when Carpe Diem, his homemade 18-foot-long rocket, hurls itself heavenward with 737 pounds of thrust, shockwaves—or “mach diamonds”—surging from its supersonic exhaust.» —“A Cult of Backyard Rocketeers Keeps the Solid Fuel Burning” by Patricia Leigh Brown in Gerlach, Nevada New York Times Oct. 14, 2006. (source: Double-Tongued Dictionary)
Further reading
Sean in Oneonta, New York, says that when he was growing up in New Jersey, his family would pile in the car and set off on a surprise adventure, whether a short distance or long, and the kids would be told only that they were going on Buxtehude...
Amanda in Reno, Nevada, has a dispute with her husband. Is it okay to ask if something is any comfortable? This is part of a complete episode.
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