To give birth to Pumbaa is to push out a huge log ... to have a shit ... It's big, brown and smelly just like Pumbaa from The Lion King ... think of Pumbaa being born.
A word for something when you can't remember what it was called. It can be used in place of all of the different types of words. It's first recorded use was when JohnTron said to Egoraptor, "It's a Pumbloom!", when he was referring to a Whismer.
Example 1:
Guy1: Dude, look at those pumblooms on that building!
Guy2: The what?
Guy1: Those things running up and down that support the bulding.
Guy2: You mean fucking columns!?!?
Example 2:
Arin: Oh, dude, look, it's a Whismer.
John: Oh! It's a pumbloom!
Arin: Remember the episode where Ash caught a pumbloom?
John: Dude...
Arin: NO!!!!!!!!!