Gack 

A great and loyal friend, a super talented artist and also really funny and kind

I love gack /p

Gack by Ziolaa November 29, 2022

Gack 

Something truly unhealthy yet shallowly rewarding.

Get some gack while you are at the shop: NikNaks, Starbars - all the major food groups.

Gack by Old Moore's Balzac December 10, 2022

gack 

A dark substance composed of melting snow, dirt, spilled beer, and a powerful mix of other excretions and spillings that stained SUNY @ Oswego students' shoes/boots after an evening imbibing at such places as Broadwell's and Buckland's (mid 80's through early 90's).

Doug: Yo, Dave, what the fuck is on your boots?

Dave: It's gack from Broadwell's last night.

gack by MoshKing88 March 10, 2023

gack 

a person who can’t handle his alcohol and prefers overweight women

oh no thats his 5th beer, he will probably be a gack and try plug a fatty tonight

gack by handlemart42 July 24, 2023

Gack 

Acronym: God-Awful Cornholed Kook

Usually referring to a person who participates in anti-social behavior. Can refer to, but is not limited to:

-Internet Trolls
-Anti-Furries
-Bloxheads (Toxic Roblox Players)
-Stans (Especially the ones obsessed with authoritarian/fascist/terroristic ideologies)
-Etc.

"That user there? I heard he's an anti-furry."
"Great, another screwball gack on the loose."

Gack by BarrelOfRadioactiveIceCream July 18, 2024

Gack 

A Synonym Of Back, Can Be Used In any Situation, However, Do Not Confuse This With The Adjective Gackful, Which Can Mean "Best, Great, Good"

"Man, Its so Democratically GACK"

Gack by Myballsitchmore December 12, 2024

GACK! 

A word or sound muttered/or written by Professors of Anatomy and Physiology when proper terminlogy is not used. Also used un situations of extreme exacerbation.

Student Answer: Gluteus Med.
Professor Commentary on test: GACK! This is not proper terminology.

"GACK!, be quiet now! Or I will leave!"

GACK! by Rojay November 30, 2006