It's an elephant that you keep as a pet with the sole purpose of using it as an umbrella. You walk around underneath it, and it shields you from the rain.

When you find yourself tired of carrying an umbrella and you just can't be bothered, one should go and buy an umbrelephant.

They are particularly popular in Seattle, Washington where it rains daily.
Sam: "Shit, man, I forgot my umbrella and it is pouring outside!"

Zach: "No need to worry, Sam, I'll get my umbrelephant. We will walk under him together and he will shield us from the rain!"

Sam: "Sweet, I need an umbrelephant!"
by Zach-The-Fucking-Man-Lynn September 15, 2011
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