Simple past tense and past participle of malfunction.(verb)
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Use "malfunctioned" in a sentence
"How do they know the machine 'malfunctioned' - isnt a slot machine supposed to be random?"
"Those servers (which were lodged in the basement of a bank in Chattanooga, Tennessee) mysteriously "malfunctioned" during a critical period in the deep night of the election when a 200,000-vote exit poll margin for John Kerry somehow morphed into a victory for Bush/Rove."
"Call me foolish - but if I was driving a vehicle that "malfunctioned" and "hit a curb", I might pause for a moment to inspect my vehicle to see what happened."