It's almost an onomatopoeia.
Also, I've used google language tools for gnome and elf.
Elf = Elf Gnome=Kabouter
The #1 alternative translation for Elf is also kabouter. The #1 alternative for Gnome is aardmannetje which means small yard man. OK. Not unreasonable.
So, I put kabouter in Dutch to English to see how that maps... Gnome! or Brownie? What's a brownie? Other than a delicious chocolatey treat or a young girl scout? And kobold? Huh.
They must all be in this picture somewhere...