lingo

noun2

1. •
   An Aboriginal language.

   • The huntsman spoke Davey’s lingo. — 1937
2. •
   (informal) Language, especially language peculiar to a particular group, field, or region; jargon or a dialect.

   • [...] I have Thoughts to tarry a small Matter in Town, to learn somewhat of your Lingo first, before I cross the Seas. — 1700