Before(Book 1): Clumsy, forgetful, few to no close friends, toad for a pet
1. He killed Nagini, Voldemort's snake, with the Gryffindor sword, whilst his head ablaze.
2. Stood up to Voldemort, saying boldly he wouldn't join them until 'Hell freezes over'.
3. He kept recruiting Dumbledore's Army even after Harry, Ron and Hermione had left.
I just saw 'Hiccup' in How to Train Your Dragon 2... Longbottomed again!
Derived from the character Neville Longbottom in the Harry Potter series.
B: Yeah it's him.
A: OMG really? How did he—
B: He got longbottomed.
Can also describe someone becoming very badass.
"Nah i havn't why?"
"Hiccup totally gets Longbottomed!"