A cat that naturally looks grumpy. His full name is Tartar sauce, but his fame on the internet site reddit.com sparked the nick name grumpy cat. A subsequent video on youtube garnered several million views, which cemented grumpy cat's place as the most widely loved feline.

The grumpy look on his face is likely due to inbreeding, but his brother pokey does not share the same facial expression.

Grumpy cat has appeared on several television newscasts, has an entire subreddit to his name (/tard) and even clothing which features his face.
Person one: hey man have you seen that picture of the cat that looks upset?

Person two: HIS NAME IS GRUMPY CAT! Get it tight or get out
by So_Many_Tapirs November 20, 2012
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A female cat named Tarder Sauce, who lots of people think is male. She has feline dwarfism, and a brother cat named Pokey.

Grumpy Cat is pure awesomeness.
Will-"Grumpy Cat is the best! He's so cool!"

Dalia- "Dude, no! Grumpy Cat is a girl, duh!"

Insurance Salesperson- *in a perky scary voice* - "Hello! Would you like -"

Grumpy Cat - "No."

Random Person - "Oh no! My iPod/iPhone just died! Now I can't take selfies!!!!!"

Grumpy Cat - "Good."

It is a goal of mine to meet Grumpy Cat aka Tarder Sauce. :) this is my first definition, hope you like it!

Grumpy Cat- " No."
by wait, what?! definitions June 28, 2013
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Grumpy Cat is a cat who always has a sarcastic or negative comment on something.
He is also the meme lord.
All hail Grumpy Cat.
Im having such a nice day!
Grumpy Cat: No.
by purple237 March 31, 2016
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A cat that has a facial deformity; has taken the world by storm
"I love Grumpy Cat!! He is so cute!!"
by ojmayo8 November 22, 2016
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When you tie up a girl and you're going down on her and she's just about to cum and, just before she does, you pull away and quit and "meow" like a grumpy cat.
This girl was so pissed because I gave her the grumpy cat.
by cmahoney September 28, 2014
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An insanely alcoholic beverage comprised of 2 shots of Vodka, 2 shots Bacardi 151, 2 shots of Gin, and 2 1\2 cups of cranberry juice.
Mr.: Hey, wanna throw down The Grumpy Cat?

Ms: Hell yeah, let's get trashed!
by Capt. Crump July 11, 2013
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the subject of many, many memes.
Grumpy cat's takeover of the internet is still going - it's memewashing people!
by bobthechez January 13, 2019
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