red mushroom n.— «A preliminary investigation also found that the train’s braking system was not defective and that the operator did not press the “red mushroom”—Muni parlance for the bright red button on the operator’s...
red mushroom n.— «A preliminary investigation also found that the train’s braking system was not defective and that the operator did not press the “red mushroom”—Muni parlance for the bright red button on the operator’s...
