Grimer (in Japanese: ベトベター “Betbeter”) is a Poison-type Pokémon. Grimer evolves into Muk (in Japanese: ベトベトン “Betbeton”) at level 38, where it remains a Poison-type. There is currently no way to Mega-evolve Muk.
Both Grimer and Muk are termed the “Sludge Pokémon”. Basically, Grimer is just a pile of crap. Muk is an even bigger, festering pile of excrement.

Q: “What are you going to the Con dressed as?” A: I think I will show up as a huge, putrid pile of human sewage!
My favorite Grimer/Muk nickname is “The-95-Feces” – which is a play on words about the famous “Ninety-Five Theses”. History tells us that the Protestant reformer Martin Luther nailed his “ninety-five theses” of to the door of the Catholic Church in protest. (Readers: Please know I am NOT making fun of religion here, just having my fun with wordplay.)
If you are not big on historical references, then you could name them after any type of excrement or pollution. Anything that you think is a “pile of crap”, you can name a Grimer/Muk after it. I named a Muk “Obamacare” , then sent it out on the Wonder-Trade. The user on the other end would have gotten a message “Denny sent over Obamacare … take good care of Obamacare”. Lots of laughs. Really, use a name fer anything you consider to be synonymous with SHIT …
Wondertrade is also a good way to send over “Massive Dump” or “A Huge Load“, perhaps even “My-Epic-Deuce” if you are playful.
(I have not tried it, but would the name-censor allow the name “S.H.I.T.E.“?)
Another name I have used is “Blockage” after all that undigested red meat you have in your intestines. Speaking of colon blockages – McDonald’s restaurants at one time had a costumed character called “Grimace”. Coincidence? The Pokémon Grimer looks a lot like the McDonald’s character.
Grimace was at first a bad guy like the “Hamburgler”. Grimace would steal your milkshake. Maybe that is not so bad … McDonalds food (like all fast-food) is full of sugar, fat and empty calories. If you eat too much greasy fast food, you may get a Muk stuck in your bowels.
Perhaps female Grimer could be named “Polly Polyps” after what you do not want found in your colonoscopy. Speaking of — do you want to see a scan from my recent colon exam?
I sometimes give Grimer a “cute” nickname like “Stinky-Poo” or something equally playful and charming, like “Rubberturd“. You know what side-splitting funny? Fake poop.

Someone in China has the job of making “fake poop”. Does the worker ever wonder “Why Americans buy this crap?”
A name like “Prunes” might be good. Prunes are good for maintaining regularity. Also, as noted by almost every middle-schooler in history – prunes already look like a turd!
Perhaps a name like “Ca-Ca Monster” after the muppet — Cookie Monster.
Named for a sound effect: perhaps a name like “Plop Plop” would work for a little Grimer. Perhaps “Floater” might be good for your little Grimer. Names having to do with sludge or sewers could wor. Perhaps “Sewardt” as a deviation of “Stuart”. Perhaps you would laugh when my trainer throws out a Muk named “Fudge-Pack“.
On the Name Rater webpage (linked there) I did not see a lot of Grimer names that i liked. “Grimetime” and “Poo Poo” were OK, I guess. Muk names “Lahar” “Schmuk” or “Mr. Turd” might be the basis of thinking something else. Maybe we should leave with a more positive image.
May I present: “The Goddess of Regularity.”
What is the name of your piece-of-crap? Please comment!
12/20/2016
ALOLA UPDATE: There are now special Alola forms of Grimer and Muk!
Thus, You may want to experiment with more colorful names. “I-Ate-Corn” for example.
“Mean-Tweet” would be one colorful example of shit. We have all seen or received unappealing messages on Twitter and elsewhere. I almost never use Twitter because it is mostly crap. When I read these hate-filled profane messages from petulant celebrities (Katy Perry, etc.), I feel like I stepped in a Muk.
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Comments on: "Pokémon Nicknames: Grimer and Muk" (2)
Grimer does appear to be related to Grimace after all!! Growing up I always, and still do wonder what the heck is Grimace anyway?? =O A giant blob of purple milk shake gone wrong I used to think but now I’m not so sure. I do miss those CMs with all of those characters in them =(.
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Grimer is slimy fellow. When I first saw it on Pokemon, I always imagine it smelling like raw sewage.
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