There are 2 results of your search for gumby.
gumby
a pimple: Did youse know ya got a huge zit/gumby on ya hooter?
Gumby
Traditionally a tram conductor or any public Transport employee. This came from the fact that they used to wear green uniforms: Get your feet off the seat - a Gumby is coming.
Contributor's comments: This used to be used in Adelaide schools for a person thought to be not "very bright".