Gremlin (noun)

1. A mischievous and troublesome creature that causes mechanical or technical problems.
2. An imaginary creature that causes trouble or mischief.

Origin:

originates from british folklore and was first used in print in the early 20th century, possibly from the dialect word gremlins meaning "mischievous spirits or goblins".

Examples:

1. The pilot blamed the engine failure on a gremlin.
2. The computer has a gremlin that makes it crash every time I try to play a game.
3. Gremlins are known to cause trouble in airplanes and other machinery.
4. The term gremlin has come to be used as a catch-all term for any unexplained problem or malfunction.
5. Gremlins, as an imaginary creature that causes trouble or mischief, have been used as a plot device in various works of fiction.