Possibly from Old English grëmian ("to vex", "to anger"), related to German grämen and Swedish gräma ("to grieve").
gremlin (plural gremlins)
- A mythical creature reputed to be mechanically inclined and mischievously inclined to damage or dismantle machinery.
- (by extension) Any mysterious, unknown source of trouble or mischief.
- We rechecked everything, and we suspect gremlins in the database.