malfunction (malfunctions plural & 3rd person present) (malfunctioning present participle) (malfunctioned past tense & past participle )If a machine or part of the body malfunctions, it fails to work properly.
FORMAL verb
The radiation can damage microprocessors and computer memories, causing them to malfunction... V
Malfunction is also a noun., n-count
There must have been a computer malfunction.