A Big Lipped Alligator Moment refers to "the big lipped alligator scene from All Dogs Go To Heaven. This is named after the random musical number sung by a big lipped alligator towards the end of the film; a scene that comes right-the-fuck out of nowhere, has little to no bearing whatsoever in the plot, is way over the top in terms of ridiculousness (even in the context of the movie), and after it happens, no one ever speaks of it again."
In short: It refers to any and all random musical scenes that have no merit in terms of plot, are very over the top and silly, and are oddly never explained or mentioned ever.
Such scenes include:
-The dancing fire gang from Labyrinth
-The pink elephants from Dumbo
-The creepy tunnel scene from Willie Wonka and the Chocolate Factory
-And the sexually undertoned blue Gila Monster (the type of lizard is debatable) song, "If I'm Gonna Eat Somebody (It Might as Well Be You)", from Ferngully
In 'Willy Wonka' The creep-ass boat ride scene with Wonka's 'poem'
The pink elephants in Dumbo
Tom: Yeah, it was a moajor Big Lipped Alligator moment
This can also be used when you and your best friend do something completely random, decide that it makes no sense, and vow to never speak of it again.
Originally found in the Nostalgia Critic/Nostalgia Chick review of "FernGully 2," some of these moments are:
-The Pink Elephants from "Dumbo."
-The song at the very end of "All Dogs Go To Heaven."
-The tunnel scene from the Gene Wilder version of "Willy Wonka and the Chocolate Factory."
Peter: It was okay. Herp Derp.
(Then the two just start derping for a while.)
Kate: Well, that was quite a Big Lipped Alligator Moment. Let us never speak of this randomness again.