Zero.
Well, I mean, the Hatter says it in the movie but it's actually a poem called "Jabberwocky" by Lewis Carroll for
Through the Looking-Glass, and What Alice Found There which is the sequel to
Alice's Adventures in Wonderland. From the Wikipedia page: ""Jabberwocky" is considered one of the greatest nonsense poems written in English. Its playful, whimsical language has given us
nonsense words and
neologisms such as "galumphing" and "chortle"."
So yeah, since it's a nonsense poem, it's not really meant to have a meaning. It's supposed to weird and messed up and all that.
The Wikipedia page also has possible interpretations of the words in the poem so if you want to try to understand it better it's
here.