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

gack 

Methamphetamine (crank, speed). Describes the gag reflex triggered by the extreme burning sensation of the nasal passages when the drug is snorted, and the very bitter taste as it drains down the back of the throat.

The character 'Pooh-Bear' in the movie "The Salton Sea" had to have his nose surgically removed because he snorted too much gack.

gack by Anonymous July 13, 2003

gack 

Any amount of useless or unwanted stuff (usually regarding possesions)

I've got too much damn gack in my attic. Guess I'll throw something on ebay.

gack by mudpup April 24, 2006

gack 

1.A term used for the Drug Crystal Meth Amphetamine

2A some what derogatory name for person under the influence of crystal meth.

1. "They just smoked a fat bowl of gack."

or Thats some killer Gack!"
2. "That guy is a total effin gack." or "Quit being such a gack, your going to get us busted!" or "Never bring that gack over to my house again!"

gack by L8Nighter March 17, 2011

Gack 

The sound made by an individual who is in the process of sucking dick. Typically a gagging sound made from the throat.

Brenda gacks on that niggas dick because she has a terrible gag reflex.

That chicken head is always gacking choad in the park.

Gack by Catsleeze September 23, 2013

gack 

Similar to "dummy text", "text filler" or "greeking". Gack is anything used in a design as a temporary place holder before being replaced by an actual design element. For instance, filling columns of text with "Lorem ipsum dolor...", or using a textured box where an image or other design element might go in a layout.

Gack can also mean something in an image or design which serves a technical purpose that is intended to be removed in the final product, such as tracking dots on a plain wall being filmed, or a wire harness on an actor that needs to be painted out.

"We need the actual text so we can replace the gack in the layout before sending it to print."

"The VFX Artist will have to paint out all this gack that is in the shot before it can be used".

gack by Andy Somers December 15, 2018

gack 

To borrow or steal internet content from another user.

I gacked this meme from lamebrain426.

gack by florimell August 9, 2003