Gack 

noun. - Ritalin, Concerta, Vyvance, Adderall, or any other Psycho-Stimulant ADHD Drug.
verb. - the state of mind when on any psychostimulant or adhd drug; usually one listed above

noun - Dude lets buy some Gack tonight.
verb - Dude lets get gacked out.

Gack by ProjectDiesel December 17, 2008

Gack 

A word used by a fucking idiotic British person who tried to create his own language while playing video games on YouTube.

Gavin of Achievement Hunter used the word 'gack' and was promptly called a fucking idiot.

Gack by Uncle Steve The Crack Addict June 14, 2016

Gack 

Gack also spelled gach is a word to be used when something is gross unpleasant weird strange or nasty started being used in Ireland 2015 and has grown to a common word

It is a great word to add to your vocabulary

Gack

Ew that meat is gack

I saw jo pick his nose, ew that's fucking gack

That's one big spider that's so gack

Your such a gacky person

Gack by Degreeinbruh September 1, 2017

Gack 

To show incredible amounts of love to your parner via gentle cuddling kissing and being in a happy relationship

"i am going to Gack you so much tonight". "do you want to go for a sweet Gack session on the couch?"

Gack by Wintergray January 30, 2018

Gack 

A phrase used to express disgust

*Cheryl kissed him*
Simon: Gack! Get your disgusting lips off of me, pig!
Cheryl: Why?
Simon: I found out you hated anime.
Cheryl: You meanie!!! *cries*
Simon: Yeah, get the fuck out and sob all you want!
Cheryl: Cartoon porn addict!!! *continues crying*

Gack by Matt_The_Anime_Man April 24, 2020

Gack 

Gay black person

Man that guy is a gack!

Speaking straight facts there brotha!!

Gack by CreatorOfGack May 5, 2021

Gack 

The term “gack” refers to someone who wants to have hot steamy sex.

Gack! Let’s go to your room.

Gack by ProfessionalDictonary September 26, 2021