Giller 

You disapprove of something someone said, automatically making them a "Giller".
This word usually lets the other person know where you stand with their suggestion / comment / plan.
Usually used after the companion says the offending sentence but in enxtreme cases you may interuppt and say loudly and proudly "Giller"
You may also optionally add either "Thriller" or "Killer" to further add to the situation.

Situation 1

Person A: I think you should lend me a ciggerette.
Person B: No i always lend you them, you never have any
Person A: Come on i always give you them back.
Person B: Oh for god sake your a giller

Situation 2

Person A: I'm going to mess around with your sis....
Person B: YOU GILLER KILLER / YOU GILLER THRILLER
Person A: ...tem

Giller by Cainzor October 3, 2006

Giller 

FRANCE

So much WT Giller this year

Giller by Bobertus Tardation August 8, 2021

Giller Plan 

A crazy or ridiculous plan that is almost guarenteed not to be carried out

"Yo this summer we should rent a car, drive no stops to california just to get on the Tom Green show"
"dude thats such a giller plan"

Giller Plan by Colin Forde December 7, 2006

a giller 

To have sex in your friend's bathroom with a bicycle helmet on.

Man last night when we were drinking i totally pulled a giller

a giller by royburg July 25, 2008

Five gallery special 

When an incarcerated person exposes himself

"Ay Joe, did you just see that?" "Naw, what happened?" "Buddy just exposed himself to that female!" "Damn, he hit her with the five gallery special!"

Five gallery special by El Muletas August 5, 2019

Gilberting 

The distorted audio sound that occurs when one has connectivity or performance issues during live streaming or video recording. It was named after JS Gilbert, a Live Streamer who often had this issue and thus, became known for it. People all over the web now use this term.

"Excuse me, can you please refresh your browser? You're gilberting."

"I tried to stay and listen but he was gilberting so badly, he was hurting my ears."

Gilberting by AngelHillTV August 25, 2016

GillennialX 

It's when a Generation X population member behaves like ones of the Millennial generation.

David had a meltdown and felt entitled to help over a problem he was having, for a 40-year-old mature man he surely exhibited some GillennialX behavior.

GillennialX by Hixxz68 July 26, 2018