What is the meaning of Gremlin?

1. A contemptible person.

   A contemptible person.

   An imaginary creature reputed to be mischievously inclined, for example, to damage or dismantle machinery.

   1. Any mysterious, unknown source of mischief or trouble, or the problem created thereby.

      Any mysterious, unknown source of mischief or trouble, or the problem created thereby.

      A young, inexperienced surfer or skateboarder, regarded as a nuisance.

      A person regarded as similar to a fictional gremlin, in particular: mischievous, troublesome, short, or annoying.

      Source: wiktionary.org