ice missile
n. A chunk of ice that flies off the roof of a moving vehicle.
I can’t tell you how many times I saw what I call a ‘slow-motion nightmare’" on the highway, said House Minority Leader Lawrence F. Cafero, who first spearheaded the effort to ground "ice missiles" in 2001. "You can’t do anything. You’re surrounded by traffic. You’re just watching it happen.
—Keith M. Phaneuf, “First storm of 2014 tests CT's new 'flying ice' ban,” Connecticut Mirror, January 03, 2014
In another move, many motorists are unaware of a new law that will require drivers and truckers to remove the ice and snow from the roofs of their vehicles in order to avoid "ice missiles" that can come flying off their roofs.
—Christopher Keating, “Rail Fares, Minimum Wage Going Up Wednesday,” The Hartford Courant, December 30, 2013
1994 (earliest)
The Civil Aviation Authority has launched a special investigation after a block of ice from an aircraft smashed through the roof of a house at Billericay, Essex.
—“Ice Missile,” Press Association, August 13, 1994
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